  
  [1X7 [33X[0;0YUtilities for Bibliographies[133X[101X
  
  [33X[0;0YA  standard  for collecting references (in particular to mathematical texts)
  is  BibTeX  ([7Xhttps://tug.org/bibtex/[107X).  A disadvantage of BibTeX is that the
  format  of  the  data  is  specified with the use by LaTeX in mind. The data
  format is less suited for conversion to other document types like plain text
  or HTML.[133X
  
  [33X[0;0YIn  the first section we describe utilities for using data from BibTeX files
  in [5XGAP[105X.[133X
  
  [33X[0;0YIn the second section we introduce a new XML based data format BibXMLext for
  bibliographies  which seems better suited for other tasks than using it with
  LaTeX.[133X
  
  [33X[0;0YAnother section will describe utilities to deal with BibXMLext data in [5XGAP[105X.[133X

  [1X7.1 [33X[0;0YParsing BibTeX Files[133X[101X
  
  [33X[0;0YHere  are functions for parsing, normalizing and printing reference lists in
  BibTeX format. The reference describing this format is [Lam85, Appendix B].[133X
  
  [1X7.1-1 ParseBibFiles[101X
  
  [33X[1;0Y[29X[2XParseBibFiles[102X( [3Xbibfile1[103X[, [3Xbibfile2[103X[, [3X...[103X]] ) [32X function[133X
  [33X[1;0Y[29X[2XParseBibStrings[102X( [3Xstr1[103X[, [3Xstr2[103X[, [3X...[103X]] ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ylist [10X[list of bib-records, list of abbrevs, list of expansions][110X[133X
  
  [33X[0;0YThe  first  function parses the files [3Xbibfile1[103X and so on (if a file does not
  exist the extension [10X.bib[110X is appended) in BibTeX format and returns a list as
  follows:  [10X[entries,  strings, texts][110X. Here [10Xentries[110X is a list of records, one
  record  for  each  reference contained in [3Xbibfile[103X. Then [10Xstrings[110X is a list of
  abbreviations  defined  by  [10X@string[110X-entries  in  [3Xbibfile[103X and [10Xtexts[110X is a list
  which  contains  in  the  corresponding  position  the full text for such an
  abbreviation.[133X
  
  [33X[0;0YThe  second  function  does  the same, but the input is given as [5XGAP[105X strings
  [3Xstr1[103X and so on.[133X
  
  [33X[0;0YThe  records  in  [10Xentries[110X store key-value pairs of a BibTeX reference in the
  form  [10Xrec(key1  = value1, ...)[110X. The names of the keys are converted to lower
  case.  The type of the reference (i.e., book, article, ...) and the citation
  key are stored as components [10X.Type[110X and [10X.Label[110X. The records also have a [10X.From[110X
  field that says that the data are read from a BibTeX source.[133X
  
  [33X[0;0YAs an example consider the following BibTeX file.[133X
  
  [4X[32X  doc/test.bib  [32X[104X
    [4X@string{ j  = "Important Journal" }[104X
    [4X@article{ AB2000, Author=  "Fritz A. First and Sec, X. Y.", [104X
    [4XTITLE="Short", journal = j, year = 2000 }[104X
  [4X[32X[104X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27Xgddirs := DirectoriesPackageLibrary("gapdoc","doc");;[127X[104X
    [4X[25Xgap>[125X [27Xf := Filename(gddirs, "test.bib");;[127X[104X
    [4X[25Xgap>[125X [27Xbib := ParseBibFiles(f);[127X[104X
    [4X[28X[ [ rec( From := rec( BibTeX := true ), Label := "AB2000", [128X[104X
    [4X[28X          Type := "article", author := "Fritz A. First and Sec, X. Y."[128X[104X
    [4X[28X            , journal := "Important Journal", title := "Short", [128X[104X
    [4X[28X          year := "2000" ) ], [ "j" ], [ "Important Journal" ] ][128X[104X
  [4X[32X[104X
  
  [1X7.1-2 NormalizedNameAndKey[101X
  
  [33X[1;0Y[29X[2XNormalizedNameAndKey[102X( [3Xnamestr[103X ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ylist of strings and names as lists[133X
  
  [33X[1;0Y[29X[2XNormalizeNameAndKey[102X( [3Xr[103X ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ynothing[133X
  
  [33X[0;0YThe  argument  [3Xnamestr[103X  must  be  a string describing an author or a list of
  authors as described in the BibTeX documentation in [Lam85, Appendix B 1.2].
  The  function  [2XNormalizedNameAndKey[102X  returns a list of the form [ normalized
  name  string,  short  key,  long  key, names as lists]. The first entry is a
  normalized form of the input where names are written as [21Xlastname, first name
  initials[121X.  The second and third entry are the name parts of a short and long
  key  for  the  bibliography entry, formed from the (initials of) last names.
  The  fourth  entry  is  a  list of lists, one for each name, where a name is
  described  by  three  strings for the last name, the first name initials and
  the first name(s) as given in the input.[133X
  
  [33X[0;0YThe  function  [2XNormalizeNameAndKey[102X  gets  as  argument  [3Xr[103X  a  record  for  a
  bibliography  entry  as  returned  by  [2XParseBibFiles[102X ([14X7.1-1[114X). It substitutes
  [10X.author[110X  and  [10X.editor[110X  fields  of  [3Xr[103X  by their normalized form, the original
  versions are stored in fields [10X.authororig[110X and [10X.editororig[110X.[133X
  
  [33X[0;0YFurthermore  a  short  and  a  long  citation key is generated and stored in
  components [10X.printedkey[110X (only if no [10X.key[110X is already bound) and [10X.keylong[110X.[133X
  
  [33X[0;0YWe continue the example from [2XParseBibFiles[102X ([14X7.1-1[114X).[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27Xgddirs := DirectoriesPackageLibrary("gapdoc","doc");;[127X[104X
    [4X[25Xgap>[125X [27Xf := Filename(gddirs, "test.bib");;[127X[104X
    [4X[25Xgap>[125X [27Xbib := ParseBibFiles(f);;[127X[104X
    [4X[25Xgap>[125X [27XNormalizedNameAndKey(bib[1][1].author);[127X[104X
    [4X[28X[ "First, F. A. and Sec, X. Y.", "FS", "firstsec", [128X[104X
    [4X[28X  [ [ "First", "F. A.", "Fritz A." ], [ "Sec", "X. Y.", "X. Y." ] ] ][128X[104X
    [4X[25Xgap>[125X [27XNormalizeNameAndKey(bib[1][1]);[127X[104X
    [4X[25Xgap>[125X [27Xbib[1][1];[127X[104X
    [4X[28Xrec( From := rec( BibTeX := true ), Label := "AB2000", [128X[104X
    [4X[28X  Type := "article", author := "First, F. A. and Sec, X. Y.", [128X[104X
    [4X[28X  authororig := "Fritz A. First and Sec, X. Y.", [128X[104X
    [4X[28X  journal := "Important Journal", keylong := "firstsec2000", [128X[104X
    [4X[28X  printedkey := "FS00", title := "Short", year := "2000" )[128X[104X
  [4X[32X[104X
  
  [1X7.1-3 WriteBibFile[101X
  
  [33X[1;0Y[29X[2XWriteBibFile[102X( [3Xbibfile[103X, [3Xbib[103X ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ynothing[133X
  
  [33X[0;0YThis  is  the converse of [2XParseBibFiles[102X ([14X7.1-1[114X). Here [3Xbib[103X either must have a
  format as list of three lists as it is returned by [2XParseBibFiles[102X ([14X7.1-1[114X). Or
  [3Xbib[103X  can  be  a  record as returned by [2XParseBibXMLextFiles[102X ([14X7.3-4[114X). A BibTeX
  file  [3Xbibfile[103X is written and the entries are formatted in a uniform way. All
  given abbreviations are used while writing this file.[133X
  
  [33X[0;0YWe continue the example from [2XNormalizeNameAndKey[102X ([14X7.1-2[114X). The command[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27XWriteBibFile("nicer.bib", bib);[127X[104X
  [4X[32X[104X
  
  [33X[0;0Yproduces a file [11Xnicer.bib[111X as follows:[133X
  
  [4X[32X  nicer.bib  [32X[104X
    [4X@string{j = "Important Journal" }[104X
    [4X[104X
    [4X@article{ AB2000,[104X
    [4X  author =           {First, F. A. and Sec, X. Y.},[104X
    [4X  title =            {Short},[104X
    [4X  journal =          j,[104X
    [4X  year =             {2000},[104X
    [4X  authororig =       {Fritz A. First and Sec, X. Y.},[104X
    [4X  keylong =          {firstsec2000},[104X
    [4X  printedkey =       {FS00}[104X
    [4X}[104X
  [4X[32X[104X
  
  [1X7.1-4 LabelsFromBibTeX[101X
  
  [33X[1;0Y[29X[2XLabelsFromBibTeX[102X( [3Xpath[103X, [3Xkeys[103X, [3Xbibfiles[103X, [3Xstyle[103X ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ya list of pairs of strings [10X[key, label][110X[133X
  
  [33X[0;0YThis  function uses [10Xbibtex[110X to determine the ordering of a list of references
  and  a  label  for  each  entry  which is typeset in a document citing these
  references.[133X
  
  [33X[0;0YThe  argument  [3Xpath[103X  is a directory specified as string or directory object.
  The  argument  [3Xbibfiles[103X  must  be  a  list  of  files in BibTeX format, each
  specified  by  a  path  relative  to the first argument, or an absolute path
  (starting  with  [10X'/'[110X) or relative to the [5XGAP[105X roots (starting with [10X"gap://"[110X).
  The  list  [3Xkeys[103X must contain strings which occur as keys in the given BibTeX
  files.  Finally  the  string  [3Xstyle[103X must be the name of a bibliography style
  (like [10X"alpha"[110X).[133X
  
  [33X[0;0YThe  list returned by this function contains pairs [10X[key, label][110X where [10Xkey[110X is
  one  of  the entries of [3Xkeys[103X and [10Xlabel[110X is a string used for citations of the
  bibliography  entry  in a document. These pairs are ordered as the reference
  list produced by BibTeX.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27Xf := Filename(DirectoriesPackageLibrary("gapdoc","doc"), "test.bib");;[127X[104X
    [4X[25Xgap>[125X [27XLabelsFromBibTeX(".", ["AB2000"], [f], "alpha");[127X[104X
    [4X[28X[ [ "AB2000", "FS00" ] ][128X[104X
  [4X[32X[104X
  
  [1X7.1-5 InfoBibTools[101X
  
  [33X[1;0Y[29X[2XInfoBibTools[102X [32X info class[133X
  
  [33X[0;0YThe  default  level  of  this  info class is 1. Functions like [2XParseBibFiles[102X
  ([14X7.1-1[114X), [10XStringBibAs...[110X are then printing some information. You can suppress
  it by setting the level of [2XInfoBibTools[102X to 0. With level 2 there may be some
  more information for debugging purposes.[133X

  [1X7.2 [33X[0;0YThe BibXMLext Format[133X[101X
  
  [33X[0;0YBibliographical  data  in BibTeX files have the disadvantage that the actual
  data  are given in LaTeX syntax. This makes it difficult to use the data for
  anything but for LaTeX, say for representations of the data as plain text or
  HTML.  For  example:  mathematical  formulae  are  in  LaTeX [10X$[110X environments,
  non-ASCII  characters  can  be  specified  in  many strange ways, and how to
  specify URLs for links if the output format allows them?[133X
  
  [33X[0;0YHere  we propose an XML data format for bibliographical data which addresses
  these problems, it is called BibXMLext. In the next section we describe some
  tools  for  generating  (an  approximation  to) this data format from BibTeX
  data, and for using data given in BibXMLext format for various purposes.[133X
  
  [33X[0;0YThe   first   motivation   for   this   development   was  the  handling  of
  bibliographical  data  in [5XGAPDoc[105X, but the format and the tools are certainly
  useful for other purposes as well.[133X
  
  [33X[0;0YWe  started  from  a  DTD  [11Xbibxml.dtd[111X  which is publicly available, say from
  [7Xhttps://bibtexml.sf.net/[107X.   This  is  essentially  a  reformulation  of  the
  definition  of  the  BibTeX  format,  including  several of some widely used
  further fields. This has already the advantage that a generic XML parser can
  check  the  validity of the data entries, for example for missing compulsary
  fields in entries. We applied the following changes and extensions to define
  the  DTD  for BibXMLext, stored in the file [11Xbibxmlext.dtd[111X which can be found
  in the root directory of this [5XGAPDoc[105X package (and in Appendix [14XC[114X):[133X
  
  [8Xnames[108X
        [33X[0;6YLists of names in the [10Xauthor[110X and [10Xeditor[110X fields in BibTeX are difficult
        to  parse.  Here  they  must be given by a sequence of [10X<name>[110X-elements
        which  each  contain an optional [10X<first>[110X- and a [10X<last>[110X-element for the
        first and last names, respectively.[133X
  
  [8X[10X<M>[110X[8X and [10X<Math>[110X[8X[108X
        [33X[0;6YThese  elements  enclose  mathematical  formulae, the content is LaTeX
        code  (without  the [10X$[110X). These should be handled in the same way as the
        elements  with  the  same  names  in  [5XGAPDoc[105X,  see [14X3.8-2[114X and [14X3.8-1[114X. In
        particular,  simple  formulae  which  have  a  well defined plain text
        representation can be given in [10X<M>[110X-elements.[133X
  
  [8XEncoding[108X
        [33X[0;6YNote  that  in  XML  files  we  can  use  the  full  range  of unicode
        characters,  see  [7Xhttps://www.unicode.org/[107X.  All  non-ASCII characters
        should  be  specified  as  unicode characters. This makes dealing with
        special  characters  easy  for  plain  text or HTML, only for use with
        LaTeX some sort of translation is necessary.[133X
  
  [8X[10X<URL>[110X[8X[108X
        [33X[0;6YThese  elements  are  allowed  everywhere  in  the  text and should be
        represented by links in converted formats which allow this. It is used
        in  the  same  way  as  the  element with the same name in [5XGAPDoc[105X, see
        [14X3.5-5[114X.[133X
  
  [8X[10X<Alt Only="...">[110X[8X and [10X<Alt Not="...">[110X[8X[108X
        [33X[0;6YSometimes  information should be given in different ways, depending on
        the   output   format   of   the  data.  This  is  possible  with  the
        [10X<Alt>[110X-elements with the same definition as in [5XGAPDoc[105X, see [14X3.9-1[114X.[133X
  
  [8X[10X<C>[110X[8X[108X
        [33X[0;6YThis  element  should  be  used  to  protect text from case changes by
        converters (the extra [10X{}[110X characters in BibTeX title fields).[133X
  
  [8X[10X<string key="..." value="..."/>[110X[8X and [10X<value key="..."/>[110X[8X[108X
        [33X[0;6YThe  [10X<string>[110X-element defines key-value pairs which can be used in any
        field  via  the  [10X<value>[110X-element  (not  only for whole fields but also
        parts of the text).[133X
  
  [8X[10X<other type="...">[110X[8X[108X
        [33X[0;6YThis  is  a  generic  element  for  fields  which  are  otherwise  not
        supported.  An  arbitrary number of them is allowed for each entry, so
        any kind of additional data can be added to entries.[133X
  
  [8X[10X<Wrap Name="...">[110X[8X[108X
        [33X[0;6YThis generic element is allowed inside all fields. This markup will be
        just  ignored (but not the element content) by our standard tools. But
        it  can be a useful hook for introducing arbitrary further markup (and
        our tools can easily be extended to handle it).[133X
  
  [8XExtra entities[108X
        [33X[0;6YThe  DTD  defines  the  standard XML entities ([14X2.1-10[114X and the entities
        [10X [110X  (non-breakable space), [10X–[110X and [10X&copyright;[110X. Use [10X–[110X in
        page ranges.[133X
  
  [33X[0;0YFor  further  details  of  the DTD we refer to the file [11Xbibxmlext.dtd[111X itself
  which  is  shown in appendix [14XC[114X. That file also recalls some information from
  the  BibTeX  documentation  on  how the standard fields of entries should be
  used.  Which entry types and which fields are supported (and the ordering of
  the  fields  which  is  fixed  by  a DTD) can be either read off the DTD, or
  within [5XGAP[105X one can use the function [2XTemplateBibXML[102X ([14X7.3-10[114X) to get templates
  for the various entry types.[133X
  
  [33X[0;0YHere is an example of a BibXMLext document:[133X
  
  [4X[32X  doc/testbib.xml  [32X[104X
    [4X<?xml version="1.0" encoding="UTF-8"?>[104X
    [4X<!DOCTYPE file SYSTEM "bibxmlext.dtd">[104X
    [4X<file>[104X
    [4X<string key="j" value="Important Journal"/>[104X
    [4X<entry id="AB2000">
[104X
    [4X  <author>[104X
    [4X    <name><first>Fritz A.</first><last>First</last></name>[104X
    [4X    <name><first>X. Y.</first><last>Secőnd</last></name>[104X
    [4X  </author>  [104X
    [4X  The <Wrap Name="Package"> <C>F</C>ritz</Wrap> package for the [104X
    [4X         formula <M>x^y - l_{{i+1}} \rightarrow \mathbb{R}</M>[104X
    [4X  <journal><value key="j"/></journal>[104X
    [4X  <year>2000</year>[104X
    [4X  <number>13</number>[104X
    [4X  <pages>13–25</pages>[104X
    [4X  <note>Online data at <URL Text="Bla Bla Publisher">[104X
    [4X                  http://www.publish.com/~ImpJ/123#data</URL></note>[104X
    [4X  <other type="mycomment">very useful</other>[104X
    [4X
</entry>[104X
    [4X</file>[104X
    [4X[104X
  [4X[32X[104X
  
  [33X[0;0YThere  is  a  standard XML header and a [10XDOCTYPE[110X declaration referring to the
  [11Xbibxmlext.dtd[111X  DTD  mentioned  above. Local entities could be defined in the
  [10XDOCTYPE[110X  tag  as  shown  in  the example in [14X2.2-3[114X. The actual content of the
  document   is   inside  a  [10X<file>[110X-element,  it  consists  of  [10X<string>[110X-  and
  [10X<entry>[110X-elements.  Several  of  the  BibXMLext markup features are shown. We
  will use this input document for some examples below.[133X

  [1X7.3 [33X[0;0YUtilities for BibXMLext data[133X[101X

  [1X7.3-1 [33X[0;0YTranslating BibTeX to BibXMLext[133X[101X
  
  [33X[0;0YFirst  we  describe  a  tool  which  can translate bibliography entries from
  BibTeX  data  to BibXMLext [10X<entry>[110X-elements. It also does some validation of
  the  data.  In  some  cases  it  is  desirable to improve the result by hand
  afterwards  (editing  formulae, adding [10X<URL>[110X-elements, translating non-ASCII
  characters to unicode, ...).[133X
  
  [33X[0;0YSee  [2XWriteBibXMLextFile[102X  ([14X7.3-5[114X)  below  for  how  to write the results to a
  BibXMLext file.[133X
  
  [1X7.3-2 HeuristicTranslationsLaTeX2XML.Apply[101X
  
  [33X[1;0Y[29X[2XHeuristicTranslationsLaTeX2XML.Apply[102X( [3Xstr[103X ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ya string[133X
  
  [33X[1;0Y[29X[2XHeuristicTranslationsLaTeX2XML.ApplyToFile[102X( [3Xfnam[103X[, [3Xoutnam[103X] ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ynothing[133X
  
  [33X[0;0YThese  utilities  translate some LaTeX code into text in UTF-8 encoding. The
  input is given as a string [3Xstr[103X, or a file name [3Xfnam[103X, respectively. The first
  function  returns  the  translated  string.  The  second  function  with one
  argument overwrites the given file with the translated text. Optionally, the
  translated file content can be written to another file, if its name is given
  as second argument [3Xoutnam[103X.[133X
  
  [33X[0;0YThe  record  [10XHeuristicTranslationsLaTeX2XML[110X  mainly contains translations of
  LaTeX  macros  for special characters which were found in hundreds of BibTeX
  entries from MathSciNet ([7Xhttps://www.ams.org/mathscinet/[107X). Just look at this
  record  if  you  want to know how it works. It is easy to extend, and if you
  have  improvements which may be of general interest, please send them to the
  [5XGAPDoc[105X author.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27Xs := "\\\"u\\'{e}\\`e{\\ss}";;[127X[104X
    [4X[25Xgap>[125X [27XPrint(s, "\n");               [127X[104X
    [4X[28X\"u\'{e}\`e{\ss}[128X[104X
    [4X[25Xgap>[125X [27XPrint(HeuristicTranslationsLaTeX2XML.Apply(s),"\n");[127X[104X
    [4X[28Xüéèß[128X[104X
  [4X[32X[104X
  
  [1X7.3-3 StringBibAsXMLext[101X
  
  [33X[1;0Y[29X[2XStringBibAsXMLext[102X( [3Xbibentry[103X[, [3Xabbrvs[103X, [3Xvals[103X][, [3Xencoding[103X] ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ya string with XML code, or [9Xfail[109X[133X
  
  [33X[0;0YThe  argument [3Xbibentry[103X is a record representing an entry from a BibTeX file,
  as  returned  in  the first list of the result of [2XParseBibFiles[102X ([14X7.1-1[114X). The
  optional  two  arguments  [3Xabbrvs[103X  and [3Xvals[103X can be lists of abbreviations and
  substitution  strings,  as  returned as second and third list element in the
  result  of  [2XParseBibFiles[102X  ([14X7.1-1[114X). The optional argument [3Xencoding[103X specifies
  the  character encoding of the string components of [3Xbibentry[103X. If this is not
  given  it is checked if all strings are valid UTF-8 encoded strings, in that
  case it is assumed that the encoding is UTF-8, otherwise the latin1 encoding
  is assumed.[133X
  
  [33X[0;0YThe  function  [2XStringBibAsXMLext[102X  creates  XML code of an [10X<entry>[110X-element in
  [10XBibXMLext[110X  format.  The  result  is  in  UTF-8  encoding  and  contains some
  heuristic  translations,  like  splitting  name  lists,  finding  places for
  [10X<C>[110X-elements,   putting   formulae   in   [10X<M>[110X-elements,   substituting  some
  characters.  The result should always be checked and maybe improved by hand.
  Some  validity  checks  are  applied  to  the given data, for example if all
  non-optional  fields  are  given.  If  this check fails the function returns
  [9Xfail[109X.[133X
  
  [33X[0;0YIf your BibTeX input contains LaTeX markup for special characters, it can be
  convenient to translate this input with [2XHeuristicTranslationsLaTeX2XML.Apply[102X
  ([14X7.3-2[114X) or [2XHeuristicTranslationsLaTeX2XML.ApplyToFile[102X ([14X7.3-2[114X) before parsing
  it as BibTeX.[133X
  
  [33X[0;0YAs  an example we consider again the short BibTeX file [11Xdoc/test.bib[111X shown in
  the example for [2XParseBibFiles[102X ([14X7.1-1[114X).[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27Xgddirs := DirectoriesPackageLibrary("gapdoc","doc");;[127X[104X
    [4X[25Xgap>[125X [27Xf := Filename(gddirs, "test.bib");;[127X[104X
    [4X[25Xgap>[125X [27Xbib := ParseBibFiles(f);;[127X[104X
    [4X[25Xgap>[125X [27Xstr := StringBibAsXMLext(bib[1][1], bib[2], bib[3]);;[127X[104X
    [4X[25Xgap>[125X [27XPrint(str, "\n");[127X[104X
    [4X[28X<entry id="AB2000">
[128X[104X
    [4X[28X  <author>[128X[104X
    [4X[28X    <name><first>Fritz A.</first><last>First</last></name>[128X[104X
    [4X[28X    <name><first>X. Y.</first><last>Sec</last></name>[128X[104X
    [4X[28X  </author>  [128X[104X
    [4X[28X  Short[128X[104X
    [4X[28X  <journal><value key="j"/></journal>[128X[104X
    [4X[28X  <year>2000</year>[128X[104X
    [4X[28X
</entry>[128X[104X
  [4X[32X[104X
  
  [33X[0;0YThe following functions allow parsing of data which are already in BibXMLext
  format.[133X
  
  [1X7.3-4 ParseBibXMLextString[101X
  
  [33X[1;0Y[29X[2XParseBibXMLextString[102X( [3Xstr[103X[, [3Xres[103X] ) [32X function[133X
  [33X[1;0Y[29X[2XParseBibXMLextFiles[102X( [3Xfname1[103X[, [3Xfname2[103X[, [3X...[103X]] ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ya record with fields [10X.entries[110X, [10X.strings[110X and [10X.entities[110X[133X
  
  [33X[0;0YThe  first  function  gets a string [3Xstr[103X containing a [10XBibXMLext[110X document or a
  part  of  it.  It  returns  a  record  with the three mentioned fields. Here
  [10X.entries[110X  is  a  list of partial XML parse trees for the [10X<entry>[110X-elements in
  [3Xstr[103X.   The   field   [10X.strings[110X   is  a  list  of  key-value  pairs  from  the
  [10X<string>[110X-elements  in [3Xstr[103X. And [10X.strings[110X is a list of name-value pairs of the
  named entities which were used during the parsing.[133X
  
  [33X[0;0YThe  optional  argument  [3Xres[103X  can  be  the  result  of a former call of this
  function,  in  that  case  the  newly  parsed entries are added to this data
  structure.[133X
  
  [33X[0;0YThe second function [2XParseBibXMLextFiles[102X uses the first on the content of all
  files  given  by  filenames  [3Xfname1[103X  and so on. It collects the results in a
  single record.[133X
  
  [33X[0;0YAs an example we parse the file [11Xtestbib.xml[111X shown in [14X7.2[114X.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27Xgddirs := DirectoriesPackageLibrary("gapdoc","doc");;[127X[104X
    [4X[25Xgap>[125X [27Xf := Filename(gddirs, "testbib.xml");;[127X[104X
    [4X[25Xgap>[125X [27Xbib := ParseBibXMLextFiles(f);;[127X[104X
    [4X[25Xgap>[125X [27XSet(RecNames(bib));[127X[104X
    [4X[28X[ "entities", "entries", "strings" ][128X[104X
    [4X[25Xgap>[125X [27Xbib.entries;[127X[104X
    [4X[28X[ <BibXMLext entry: AB2000> ][128X[104X
    [4X[25Xgap>[125X [27Xbib.strings;[127X[104X
    [4X[28X[ [ "j", "Important Journal" ] ][128X[104X
    [4X[25Xgap>[125X [27Xbib.entities[1]; [127X[104X
    [4X[28X[ "amp", "&#38;" ][128X[104X
  [4X[32X[104X
  
  [1X7.3-5 WriteBibXMLextFile[101X
  
  [33X[1;0Y[29X[2XWriteBibXMLextFile[102X( [3Xfname[103X, [3Xbib[103X ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ynothing[133X
  
  [33X[0;0YThis function writes a BibXMLext file with name [3Xfname[103X.[133X
  
  [33X[0;0YThere  are  three  possibilities  to specify the bibliography entries in the
  argument  [3Xbib[103X.  It can be a list of three lists as returned by [2XParseBibFiles[102X
  ([14X7.1-1[114X).  Or  it can be just the first of such three lists in which case the
  other  two lists are assumed to be empty. To all entries of the (first) list
  the  function [2XStringBibAsXMLext[102X ([14X7.3-3[114X) is applied and the resulting strings
  are written to the result file.[133X
  
  [33X[0;0YThe  third  possibility is that [3Xbib[103X is a record in the format as returned by
  [2XParseBibXMLextString[102X  ([14X7.3-4[114X)  and [2XParseBibXMLextFiles[102X ([14X7.3-4[114X). In this case
  the  entries  for  the  BibXMLext  file  are  produced with [2XStringXMLElement[102X
  ([14X5.2-2[114X), and if [3Xbib[103X[10X.entities[110X is bound then it is tried to resubstitute parts
  of the string by the given entities with [2XEntitySubstitution[102X ([14X5.2-3[114X).[133X
  
  [33X[0;0YAs   an  example  we  write  back  the  result  of  the  example  shown  for
  [2XParseBibXMLextFiles[102X ([14X7.3-4[114X) to an equivalent XML file.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27Xgddirs := DirectoriesPackageLibrary("gapdoc","doc");;[127X[104X
    [4X[25Xgap>[125X [27Xf := Filename(gddirs, "testbib.xml");;[127X[104X
    [4X[25Xgap>[125X [27Xbib := ParseBibXMLextFiles(f);;[127X[104X
    [4X[25Xgap>[125X [27XWriteBibXMLextFile("test.xml", bib);[127X[104X
  [4X[32X[104X

  [1X7.3-6 [33X[0;0YBibliography Entries as Records[133X[101X
  
  [33X[0;0YFor  working with BibXMLext entries we find it convenient to first translate
  the parse tree of an entry, as returned by [2XParseBibXMLextFiles[102X ([14X7.3-4[114X), to a
  record  with  the  field names of the entry as components whose value is the
  content  of the field as string. These strings are generated with respect to
  a result type. The records are generated by the following function which can
  be customized by the user.[133X
  
  [1X7.3-7 RecBibXMLEntry[101X
  
  [33X[1;0Y[29X[2XRecBibXMLEntry[102X( [3Xentry[103X[, [3Xrestype[103X][, [3Xstrings[103X][, [3Xoptions[103X] ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ya record with fields as strings[133X
  
  [33X[0;0YThis  function  generates  a content string for each field of a bibliography
  entry  and assigns them to record components. This content may depend on the
  requested result type and possibly some given options.[133X
  
  [33X[0;0YThe  arguments are as follows: [3Xentry[103X is the parse tree of an [10X<entry>[110X element
  as  returned by [2XParseBibXMLextString[102X ([14X7.3-4[114X) or [2XParseBibXMLextFiles[102X ([14X7.3-4[114X).
  The optional argument [3Xrestype[103X describes the type of the result. This package
  supports  currently  the  types  [10X"BibTeX"[110X, [10X"Text"[110X and [10X"HTML"[110X. The default is
  [10X"BibTeX"[110X. The optional argument [3Xstrings[103X must be a list of key-value pairs as
  returned  in  the  component  [10X.strings[110X in the result of [2XParseBibXMLextString[102X
  ([14X7.3-4[114X). The argument [3Xoptions[103X must be a record.[133X
  
  [33X[0;0YIf  the  entry  contains an [10Xauthor[110X field then the result will also contain a
  component  [10X.authorAsList[110X  which  is a list containing for each author a list
  with  three entries of the form [10X[last name, first name initials, first name][110X
  (the  third  entry means the first name as given in the data). Similarly, an
  [10Xeditor[110X field is accompanied by a component [10X.editorAsList[110X.[133X
  
  [33X[0;0YThe following [3Xoptions[103X are currently supported.[133X
  
  [33X[0;0YIf [10Xoptions.fullname[110X is bound and set to [9Xtrue[109X then the full given first names
  for  authors and editors will be used, the default is to use the initials of
  the  first  names.  Also,  if [10Xoptions.namefirstlast[110X is bound and set to [9Xtrue[109X
  then  the names are written in the form [21Xfirst-name(s) last-name[121X, the default
  is the form [21Xlast-name, first-name(s)[121X.[133X
  
  [33X[0;0YIf [10Xoptions.href[110X is bound and set to [9Xfalse[109X then the [10X"BibTeX"[110X type result will
  not  use  [10X\href[110X  commands.  The  default  is  to produce [10X\href[110X commands from
  [10X<URL>[110X-elements  such  that LaTeX with the [10Xhyperref[110X package can produce links
  for them.[133X
  
  [33X[0;0YThe  content  of an [10X<Alt>[110X-element with [10XOnly[110X-attribute is included if [3Xrestype[103X
  is given in the attribute and ignored otherwise, and vice versa in case of a
  [10XNot[110X-attribute.  If  [10Xoptions.useAlt[110X is bound, it must be a list of strings to
  which  [3Xrestype[103X  is  added.  Then  an  [10X<Alt>[110X-element  with  [10XOnly[110X-attribute is
  evaluated  if  the intersection of [10Xoptions.useAlt[110X and the types given in the
  attribute  is not empty. In case of a [10XNot[110X-attribute the element is evaluated
  if this intersection is empty.[133X
  
  [33X[0;0YIf  [3Xrestype[103X is [10X"BibTeX"[110X then the string fields in the result will be recoded
  with  [2XEncode[102X  ([14X6.2-2[114X) and target [10X"LaTeX"[110X. If [10Xoptions.hasLaTeXmarkup[110X is bound
  and  set  to  [9Xtrue[109X  (for  example, because the data are originally read from
  BibTeX files), then the target [10X"LaTeXleavemarkup"[110X will be used.[133X
  
  [33X[0;0YWe use again the file shown in the example for [2XParseBibXMLextFiles[102X ([14X7.3-4[114X).[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27Xgddirs := DirectoriesPackageLibrary("gapdoc","doc");;[127X[104X
    [4X[25Xgap>[125X [27Xf := Filename(gddirs, "testbib.xml");;[127X[104X
    [4X[25Xgap>[125X [27Xbib := ParseBibXMLextFiles(f);;[127X[104X
    [4X[25Xgap>[125X [27Xe := bib.entries[1];; strs := bib.strings;;[127X[104X
    [4X[25Xgap>[125X [27XPrint(RecBibXMLEntry(e, "BibTeX", strs), "\n");[127X[104X
    [4X[28Xrec([128X[104X
    [4X[28X  From := rec([128X[104X
    [4X[28X      BibXML := true,[128X[104X
    [4X[28X      options := rec([128X[104X
    [4X[28X           ),[128X[104X
    [4X[28X      type := "BibTeX" ),[128X[104X
    [4X[28X  Label := "AB2000",[128X[104X
    [4X[28X  Type := "article",[128X[104X
    [4X[28X  author := "First, F. A. and Sec{\\H o}nd, X. Y.",[128X[104X
    [4X[28X  authorAsList := [128X[104X
    [4X[28X   [ [ "First", "F. A.", "Fritz A." ], [128X[104X
    [4X[28X      [ "Sec\305\221nd", "X. Y.", "X. Y." ] ],[128X[104X
    [4X[28X  journal := "Important Journal",[128X[104X
    [4X[28X  mycomment := "very useful",[128X[104X
    [4X[28X  note := [128X[104X
    [4X[28X   "Online data at \\href {http://www.publish.com/~ImpJ/123#data} {Bla\[128X[104X
    [4X[28X Bla Publisher}",[128X[104X
    [4X[28X  number := "13",[128X[104X
    [4X[28X  pages := "13{\\textendash}25",[128X[104X
    [4X[28X  printedkey := "FS00",[128X[104X
    [4X[28X  title := [128X[104X
    [4X[28X   "The  {F}ritz package for the \n         formula $x^y - l_{{i+1}} \[128X[104X
    [4X[28X\\rightarrow \\mathbb{R}$",[128X[104X
    [4X[28X  year := "2000" )[128X[104X
    [4X[25Xgap>[125X [27XPrint(RecBibXMLEntry(e, "HTML", strs).note, "\n");[127X[104X
    [4X[28XOnline data at Bla Bla\[128X[104X
    [4X[28X Publisher (http://www.publish.com/~ImpJ/123#data)[128X[104X
  [4X[32X[104X
  
  [1X7.3-8 AddHandlerBuildRecBibXMLEntry[101X
  
  [33X[1;0Y[29X[2XAddHandlerBuildRecBibXMLEntry[102X( [3Xelementname[103X, [3Xrestype[103X, [3Xhandler[103X ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ynothing[133X
  
  [33X[0;0YThe argument [3Xelementname[103X must be the name of an entry field supported by the
  BibXMLext  format, the name of one of the special elements [10X"C"[110X, [10X"M"[110X, [10X"Math"[110X,
  [10X"URL"[110X  or  of  the  form  [10X"Wrap:myname"[110X  or  any string [10X"mytype"[110X (which then
  corresponds  to entry fields [10X<other type="mytype">[110X). The string [10X"Finish"[110X has
  an exceptional meaning, see below.[133X
  
  [33X[0;0Y[3Xrestype[103X  is  a  string  describing  the result type for which the handler is
  installed, see [2XRecBibXMLEntry[102X ([14X7.3-7[114X).[133X
  
  [33X[0;0YFor  both  arguments,  [3Xelementname[103X  and [3Xrestype[103X, it is also possible to give
  lists of the described ones for installing several handler at once.[133X
  
  [33X[0;0YThe  argument  [3Xhandler[103X  must  be  a function with five arguments of the form
  [3Xhandler[103X[10X(entry,  r, restype, strings, options)[110X. Here [3Xentry[103X is a parse tree of
  a  BibXMLext  [10X<entry>[110X-element,  [3Xr[103X  is  a  node  in  this tree for an element
  [3Xelementname[103X,   and   [3Xrestype[103X,  [3Xstrings[103X  and  [3Xoptions[103X  are  as  explained  in
  [2XRecBibXMLEntry[102X ([14X7.3-7[114X). The function should return a string representing the
  content  of  the  node  [3Xr[103X.  If  [3Xelementname[103X is of the form [10X"Wrap:myname"[110X the
  handler is used for elements of form [10X<Wrap Name="myname">...</Wrap>[110X.[133X
  
  [33X[0;0YIf  [3Xelementname[103X  is  [10X"Finish"[110X the handler should look like above except that
  now  [3Xr[103X  is  the record generated by [2XRecBibXMLEntry[102X ([14X7.3-7[114X) just before it is
  returned.  Here  the  handler  should  return  nothing.  It  can  be used to
  manipulate  the  record  [3Xr[103X,  for  example  for  changing the encoding of the
  strings or for adding some more components.[133X
  
  [33X[0;0YThe  installed  handler  is called by [10XBuildRecBibXMLEntry([110X[3Xentry[103X, [3Xr[103X, [3Xrestype[103X,
  [3Xstrings[103X,  [3Xoptions[103X[10X)[110X.  The  string  for the whole content of an element can be
  generated   by   [10XContentBuildRecBibXMLEntry([110X[3Xentry[103X,   [3Xr[103X,   [3Xrestype[103X,  [3Xstrings[103X,
  [3Xoptions[103X[10X)[110X.[133X
  
  [33X[0;0YWe  continue  the  example from [2XRecBibXMLEntry[102X ([14X7.3-7[114X) and install a handler
  for  the [10X<Wrap Name="Package">[110X-element such that LaTeX puts its content in a
  sans serif font.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27XAddHandlerBuildRecBibXMLEntry("Wrap:Package", "BibTeX",[127X[104X
    [4X[25X>[125X [27Xfunction(entry,  r, restype,  strings, options)[127X[104X
    [4X[25X>[125X [27X  return Concatenation("\\textsf{", ContentBuildRecBibXMLEntry([127X[104X
    [4X[25X>[125X [27X            entry, r, restype,  strings, options), "}");[127X[104X
    [4X[25X>[125X [27Xend);[127X[104X
    [4X[25Xgap>[125X [27X[127X[104X
    [4X[25Xgap>[125X [27XPrint(RecBibXMLEntry(e, "BibTeX", strs).title, "\n");[127X[104X
    [4X[28XThe \textsf{ {F}ritz} package for the [128X[104X
    [4X[28X         formula $x^y - l_{{i+1}} \rightarrow \mathbb{R}$[128X[104X
    [4X[25Xgap>[125X [27XPrint(RecBibXMLEntry(e, "Text", strs).title, "\n");  [127X[104X
    [4X[28XThe  Fritz package for the [128X[104X
    [4X[28X         formula x^y - l_{i+1} → R[128X[104X
    [4X[25Xgap>[125X [27XAddHandlerBuildRecBibXMLEntry("Wrap:Package", "BibTeX", "Ignore");[127X[104X
  [4X[32X[104X
  
  [1X7.3-9 StringBibXMLEntry[101X
  
  [33X[1;0Y[29X[2XStringBibXMLEntry[102X( [3Xentry[103X[, [3Xrestype[103X][, [3Xstrings[103X][, [3Xoptions[103X] ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ya string[133X
  
  [33X[0;0YThe  arguments  of  this function have the same meaning as in [2XRecBibXMLEntry[102X
  ([14X7.3-7[114X) but the return value is a string representing the bibliography entry
  in a format specified by [3Xrestype[103X (default is [10X"BibTeX"[110X).[133X
  
  [33X[0;0YCurrently, the following cases for [3Xrestype[103X are supported:[133X
  
  [8X[10X"BibTeX"[110X[8X[108X
        [33X[0;6YA string with BibTeX source code is generated.[133X
  
  [8X[10X"Text"[110X[8X[108X
        [33X[0;6YA  text  representation  of  the  text is returned. If [10Xoptions.ansi[110X is
        bound  it  must be a record. The components must have names [10XBib_Label[110X,
        [10XBib_author[110X,  and so on for all fieldnames. The value of each component
        is  a  pair  of strings which will enclose the content of the field in
        the result or the first of these strings in which case the default for
        the  second  is  [10XTextAttr.reset[110X (see [2XTextAttr[102X ([14X6.1-2[114X)). If you give an
        empty record here, some default ANSI color markup will be used.[133X
  
  [8X[10X"HTML"[110X[8X[108X
        [33X[0;6YAn HTML representation of the bibliography entry is returned. The text
        from  each  field  is enclosed in markup (mostly [10X[110X-elements) with
        the  [10Xclass[110X  attribute  set  to  the field name. This allows a detailed
        layout of the code via a style sheet file. If [10Xoptions.MathJax[110X is bound
        and  has the value [9Xtrue[109X then formulae are encoded for display on pages
        with [5XMathJax[105X support.[133X
  
  [8X[10X"Markdown"[110X[8X[108X
        [33X[0;6YA  representation  of  the  bibliography  entry  in Markdown format is
        returned. If [10Xoptions.markup[110X is bound it must be a record which is used
        in the same way as [10Xoptions.ansi[110X for the [10X"Text"[110X version.[133X
  
  [33X[0;0YWe use again the file shown in the example for [2XParseBibXMLextFiles[102X ([14X7.3-4[114X).[133X
  
  [4X[32X  Example  [32X[104X
    [4X[28X   edited for readability [128X[104X
    [4X[25Xgap>[125X [27Xgddirs := DirectoriesPackageLibrary("gapdoc","doc");;[127X[104X
    [4X[25Xgap>[125X [27Xf := Filename(gddirs, "testbib.xml");;[127X[104X
    [4X[25Xgap>[125X [27Xbib := ParseBibXMLextFiles(f);;[127X[104X
    [4X[25Xgap>[125X [27Xe := bib.entries[1];; strs := bib.strings;;[127X[104X
    [4X[25Xgap>[125X [27Xebib := StringBibXMLEntry(e, "BibTeX", strs);;[127X[104X
    [4X[25Xgap>[125X [27XPrintFormattedString(ebib);[127X[104X
    [4X[28X@article{ AB2000,[128X[104X
    [4X[28X  author =           {First, F. A. and Sec{\H o}nd, X. Y.},[128X[104X
    [4X[28X  title =            {The  {F}ritz  package  for  the formula $x^y -[128X[104X
    [4X[28X                      l_{{i+1}} \rightarrow \mathbb{R}$},[128X[104X
    [4X[28X  journal =          {Important Journal},[128X[104X
    [4X[28X  number =           {13},[128X[104X
    [4X[28X  year =             {2000},[128X[104X
    [4X[28X  pages =            {13{\textendash}25},[128X[104X
    [4X[28X  note =             {Online          data          at         \href[128X[104X
    [4X[28X                      {http://www.publish.com/~ImpJ/123#data}   {Bla[128X[104X
    [4X[28X                      Bla Publisher}},[128X[104X
    [4X[28X  mycomment =        {very useful},[128X[104X
    [4X[28X  printedkey =       {FS00}[128X[104X
    [4X[28X}[128X[104X
    [4X[25Xgap>[125X [27Xetxt := StringBibXMLEntry(e, "Text", strs);;      [127X[104X
    [4X[25Xgap>[125X [27Xetxt := SimplifiedUnicodeString(Unicode(etxt), "latin1", "single");;[127X[104X
    [4X[25Xgap>[125X [27Xetxt := Encode(etxt, GAPInfo.TermEncoding);;                        [127X[104X
    [4X[25Xgap>[125X [27XPrintFormattedString(etxt);[127X[104X
    [4X[28X[FS00]  First,  F.  A.  and Second, X. Y., The Fritz package for the[128X[104X
    [4X[28Xformula  x^y  -  l_{i+1}  ?  R, Important Journal, 13 (2000), 13-25,[128X[104X
    [4X[28X(Online        data        at        Bla        Bla        Publisher[128X[104X
    [4X[28X(http://www.publish.com/~ImpJ/123#data)).[128X[104X
    [4X[28X[128X[104X
    [4X[25Xgap>[125X [27Xehtml := StringBibXMLEntry(e, "HTML", strs, rec(MathJax := true));;[127X[104X
    [4X[25Xgap>[125X [27Xehtml := Encode(Unicode(ehtml), GAPInfo.TermEncoding);;[127X[104X
    [4X[25Xgap>[125X [27XPrintFormattedString(ehtml);[127X[104X
    [4X[28X
[128X[104X
    [4X[28X[FS00]   [128X[104X
    [4X[28X First, F. A. and Secőnd, X. Y.,[128X[104X
    [4X[28X The  Fritz package for the [128X[104X
    [4X[28X         formula \(x^y - l_{{i+1}} \rightarrow \mathbb{R}\),[128X[104X
    [4X[28X Important Journal [128X[104X
    [4X[28X(13)[128X[104X
    [4X[28X (2000),[128X[104X
    [4X[28X 13–25
[128X[104X
    [4X[28X(Online data at [128X[104X
    [4X[28XBla Bla [128X[104X
    [4X[28XPublisher (http://www.publish.com/~ImpJ/123#data)).[128X[104X
    [4X[28X
[128X[104X
    [4X[28X[128X[104X
  [4X[32X[104X
  
  [33X[0;0YThe  following  command may be useful to generate completly new bibliography
  entries in BibXMLext format. It also informs about the supported entry types
  and field names.[133X
  
  [1X7.3-10 TemplateBibXML[101X
  
  [33X[1;0Y[29X[2XTemplateBibXML[102X( [[3Xtype[103X] ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ylist of types or string[133X
  
  [33X[0;0YWithout  an  argument  this  function  returns a list of the supported entry
  types in BibXMLext documents.[133X
  
  [33X[0;0YWith  an  argument [3Xtype[103X of one of the supported types the function returns a
  string  which  is  a  template for a corresponding BibXMLext entry. Optional
  field  elements  have  a [10X*[110X appended. If an element has the word [10XOR[110X appended,
  then  either this element or the next must/can be given, not both. If [10XAND/OR[110X
  is  appended then this and/or the next can/must be given. Elements which can
  appear several times have a [10X+[110X appended. Places to fill are marked by an [10XX[110X.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27XTemplateBibXML();[127X[104X
    [4X[28X[ "article", "book", "booklet", "conference", "inbook", [128X[104X
    [4X[28X  "incollection", "inproceedings", "manual", "mastersthesis", "misc", [128X[104X
    [4X[28X  "phdthesis", "proceedings", "techreport", "unpublished" ][128X[104X
    [4X[25Xgap>[125X [27XPrint(TemplateBibXML("inbook"));[127X[104X
    [4X[28X<entry id="X"><inbook>[128X[104X
    [4X[28X  <author>[128X[104X
    [4X[28X    <name><first>X</first><last>X</last></name>+[128X[104X
    [4X[28X  </author>OR[128X[104X
    [4X[28X  <editor>[128X[104X
    [4X[28X    <name><first>X</first><last>X</last></name>+[128X[104X
    [4X[28X  </editor>[128X[104X
    [4X[28X  X[128X[104X
    [4X[28X  <chapter>X</chapter>AND/OR[128X[104X
    [4X[28X  <pages>X</pages>[128X[104X
    [4X[28X  <publisher>X</publisher>[128X[104X
    [4X[28X  <year>X</year>[128X[104X
    [4X[28X  <volume>X</volume>*OR[128X[104X
    [4X[28X  <number>X</number>*[128X[104X
    [4X[28X  <series>X</series>*[128X[104X
    [4X[28X  <type>X</type>*[128X[104X
    [4X[28X  
X
*[128X[104X
    [4X[28X  <edition>X</edition>*[128X[104X
    [4X[28X  <month>X</month>*[128X[104X
    [4X[28X  <note>X</note>*[128X[104X
    [4X[28X  <key>X</key>*[128X[104X
    [4X[28X  <annotate>X</annotate>*[128X[104X
    [4X[28X  <crossref>X</crossref>*[128X[104X
    [4X[28X  <abstract>X</abstract>*[128X[104X
    [4X[28X  <affiliation>X</affiliation>*[128X[104X
    [4X[28X  <contents>X</contents>*[128X[104X
    [4X[28X  <copyright>X</copyright>*[128X[104X
    [4X[28X  <isbn>X</isbn>*OR[128X[104X
    [4X[28X  <issn>X</issn>*[128X[104X
    [4X[28X  <keywords>X</keywords>*[128X[104X
    [4X[28X  <language>X</language>*[128X[104X
    [4X[28X  <lccn>X</lccn>*[128X[104X
    [4X[28X  <location>X</location>*[128X[104X
    [4X[28X  <mrnumber>X</mrnumber>*[128X[104X
    [4X[28X  <mrclass>X</mrclass>*[128X[104X
    [4X[28X  <mrreviewer>X</mrreviewer>*[128X[104X
    [4X[28X  <price>X</price>*[128X[104X
    [4X[28X  <size>X</size>*[128X[104X
    [4X[28X  <url>X</url>*[128X[104X
    [4X[28X  <category>X</category>*[128X[104X
    [4X[28X  <other type="X">X</other>*+[128X[104X
    [4X[28X</inbook></entry>[128X[104X
  [4X[32X[104X

  [1X7.4 [33X[0;0YGetting BibTeX entries from [5XMathSciNet[105X[101X[1X[133X[101X
  
  [33X[0;0YWe      provide      utilities     to     access     the     [5X     MathSciNet[105X
  ([7Xhttps://www.ams.org/mathscinet/[107X)  data  base  from  within  GAP.  The first
  condition  for  this  to  work  is  that one of the programs [10Xwget[110X or [10Xcurl[110X is
  installed  on  your  system.  The  second  is, of course, that you use these
  functions from a computer which has access to [5XMathSciNet[105X.[133X
  
  [33X[0;0YPlease note, that the usual license for [5XMathSciNet[105X access does not allow for
  automated searches in the database. Therefore, only use the [2XSearchMR[102X ([14X7.4-1[114X)
  function for single queries, as you would do using your webbrowser.[133X
  
  [1X7.4-1 SearchMR[101X
  
  [33X[1;0Y[29X[2XSearchMR[102X( [3Xqurec[103X ) [32X function[133X
  [33X[1;0Y[29X[2XSearchMRBib[102X( [3Xbib[103X ) [32X function[133X
  [6XReturns:[106X  [33X[0;10Ya list of strings, a string or [9Xfail[109X[133X
  
  [33X[0;0YThe  first  function  [2XSearchMR[102X  provides  the  same functionality as the Web
  interface  [5X  MathSciNet[105X ([7Xhttps://www.ams.org/mathscinet/[107X). The query strings
  must  be  given as a record, and the following components of this record are
  recognized:    [10XAuthor[110X,    [10XAuthorRelated[110X,    [10XTitle[110X,    [10XReviewText[110X,   [10XJournal[110X,
  [10XInstitutionCode[110X,   [10XSeries[110X,   [10XMSCPrimSec[110X,   [10XMSCPrimary[110X,  [10XMRNumber[110X,  [10XAnywhere[110X,
  [10XReferences[110X and [10XYear[110X.[133X
  
  [33X[0;0YFurthermore,  the component [10Xtype[110X can be specified. It can be one of [10X"bibtex"[110X
  (the  default  if not given), [10X"pdf"[110X, [10X"html"[110X and probably others. In the last
  cases  the  function  returns  a  string  with  the  content of the web page
  returned by [5XMathSciNet[105X. In the first case the [5XMathSciNet[105X interface returns a
  web  page  with BibTeX entries, for convenience this function returns a list
  of strings, each containing the BibTeX text for a single result entry.[133X
  
  [33X[0;0YIf  a  component [10Xuri[110X is bound and set to [9Xtrue[109X the function does not actually
  send  a  request to [5XMathSciNet[105X but returns a string with the URI that can be
  called for the request.[133X
  
  [33X[0;0YThe  format  of  a  [10X.Year[110X  component  can  be  either  a  four digit number,
  optionally  preceded  by one of the characters [10X'<'[110X, [10X'>'[110X or [10X'='[110X, or it can be
  two four digit numbers separated by a [10X-[110X to specify a year range.[133X
  
  [33X[0;0YThe  function [2XSearchMRBib[102X gets a record of a parsed BibTeX entry as input as
  returned  by  [2XParseBibFiles[102X  ([14X7.1-1[114X) or [2XParseBibStrings[102X ([14X7.1-1[114X). It tries to
  generate  some  sensible  input from this information for [2XSearchMR[102X and calls
  that function.[133X
  
  [4X[32X  Example  [32X[104X
    [4X[25Xgap>[125X [27Xll := SearchMR(rec(Author:="Gauss", Title:="Disquisitiones"));;[127X[104X
    [4X[25Xgap>[125X [27Xll2 := List(ll, HeuristicTranslationsLaTeX2XML.Apply);;[127X[104X
    [4X[25Xgap>[125X [27Xbib := ParseBibStrings(Concatenation(ll2));;[127X[104X
    [4X[25Xgap>[125X [27Xbibxml := List(bib[1], StringBibAsXMLext);;[127X[104X
    [4X[25Xgap>[125X [27Xbib2 := ParseBibXMLextString(Concatenation(bibxml));;[127X[104X
    [4X[25Xgap>[125X [27Xfor b in bib2.entries do [127X[104X
    [4X[25X>[125X [27X         PrintFormattedString(StringBibXMLEntry(b, "Text")); od;     [127X[104X
    [4X[28X[Gau95]   Gauss,   C.   F.,  Disquisitiones  arithmeticae,  Academia[128X[104X
    [4X[28XColombiana   de  Ciencias  Exactas,  Físicas  y  Naturales,  Bogotá,[128X[104X
    [4X[28XColección   Enrique   Pérez   Arbeláez   [Enrique   Pérez   Arbeláez[128X[104X
    [4X[28XCollection],  10  (1995), xliv+495 pages, (Translated from the Latin[128X[104X
    [4X[28Xby  Hugo  Barrantes  Campos,  Michael Josephy and Ángel Ruiz Zúñiga,[128X[104X
    [4X[28XWith a preface by Ruiz Zúñiga).[128X[104X
    [4X[28X[128X[104X
    [4X[28X[Gau86]  Gauss, C. F., Disquisitiones arithmeticae, Springer-Verlag,[128X[104X
    [4X[28XNew  York  (1986),  xx+472  pages, (Translated and with a preface by[128X[104X
    [4X[28XArthur  A.  Clarke,  Revised  by  William  C.  Waterhouse, Cornelius[128X[104X
    [4X[28XGreither and A. W. Grootendorst and with a preface by Waterhouse).[128X[104X
    [4X[28X[128X[104X
    [4X[28X[Gau66]  Gauss,  C. F., Disquisitiones arithmeticae, Yale University[128X[104X
    [4X[28XPress, New Haven, Conn.-London, Translated into English by Arthur A.[128X[104X
    [4X[28XClarke, S. J (1966), xx+472 pages.[128X[104X
    [4X[28X[128X[104X
  [4X[32X[104X
  
