@prefix :  <http://example.org/x/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .
 
 _:ont a owl:Ontology .

 :p rdf:type owl:ObjectProperty .
 :c rdf:type owl:Class .
 :x rdf:type owl:NamedIndividual .
 :y rdf:type owl:NamedIndividual .

 :x :p :y.
 :y rdf:type :c.
 :x :p _:y.
 _:y rdf:type :c.
 :z rdf:type _:x.

_:x rdf:type owl:Restriction.
_:x owl:onProperty :p.
_:x owl:someValuesFrom :c .