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

:Alice a :Person ;
    :name "Alice" ;
    :knows :Bob .

:Bob a :Person ;
    :name "Bob" .

# No name for KO to trigger validation error
:ko a :Person ;
    :knows :ko .

# Knows KO to trigger validation error
:ko1 a :Person ;
    :name "KO1" ;
    :knows :ko .
