<http://caligraph.org/ontology/Product_introduced_in_the_1950s>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_20th_century> .
<http://caligraph.org/ontology/Product_introduced_in_1950>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_the_1950s>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/2002/07/owl#Class> .
<http://caligraph.org/ontology/Product_introduced_in_1959>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_1955>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_the_1950s>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://en.wikipedia.org/wiki/Category:Products_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_1953>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_1952>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_the_1950s>	<http://www.w3.org/2000/01/rdf-schema#label>	"Product introduced in the 1950s" .
<http://caligraph.org/ontology/Product_introduced_in_1958>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_1957>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_1951>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_1954>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .
<http://caligraph.org/ontology/Product_introduced_in_1956>	<http://www.w3.org/2000/01/rdf-schema#subClassOf>	<http://caligraph.org/ontology/Product_introduced_in_the_1950s> .