@prefix : <http://example/> .
@prefix  rdfs:   <http://www.w3.org/2000/01/rdf-schema#> .

:x1 rdfs:label "a"  .
:x2 rdfs:label "z" .
:x3 rdfs:label "aaaZZZbbb" .
:x4 rdfs:label "zzz" .

:y1 :p "zzz" .
