prefix :       <http://example.org/>
prefix xsd:    <http://www.w3.org/2001/XMLSchema#>

abstract :A {
  :p [ "A" ] ;
}

:B extends @:A {
  :p [ "B" ]
}

:C extends @:A {
  :p [ "C" ]
}

:S extends @:B extends @:C {
  :p [ "S" ]
}
