<http://caligraph.org/ontology/Piano_quartet>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Musical_quartet> .
<http://caligraph.org/ontology/String_quartet>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Musical_quartet> .
<http://caligraph.org/ontology/Musical_quartet>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://en.wikipedia.org/wiki/Category:Musical_quartets> .
<http://caligraph.org/ontology/Musical_quartet>	<http://www.w3.org/2000/01/rdf-schema#label>	"Musical quartet" .
<http://caligraph.org/ontology/Musical_quartet>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Quartet> .
<http://caligraph.org/ontology/Vocal_quartet>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Musical_quartet> .
<http://caligraph.org/ontology/Musical_quartet>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/2002/07/owl#Class> .