@prefix ex: <http://example.org/ns#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
@prefix owl: <http://www.w3.org/2002/07/owl#> .

_:rdfs09 a owl:Ontology .
 
ex:c a owl:Class .
ex:d a owl:Class .
ex:e a owl:Class .
ex:f a owl:Class .
ex:a a owl:NamedIndividual .

ex:c rdfs:subClassOf ex:d .
ex:d rdfs:subClassOf ex:e .
ex:e rdfs:subClassOf ex:f .

ex:a rdf:type ex:c .
