<http://caligraph.org/ontology/Maritime_incident_in_April_1820>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/2002/07/owl#Class> .
<http://caligraph.org/ontology/Maritime_incident_in_April_1820>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Maritime_incident_in_1820> .
<http://caligraph.org/ontology/Maritime_incident_in_April_1820>	<http://www.w3.org/2000/01/rdf-schema#label>	"Maritime incident in April 1820" .
<http://caligraph.org/ontology/Maritime_incident_in_April_1820>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://en.wikipedia.org/wiki/Category:Maritime_incidents_in_April_1820> .