About: http://webisa.webdatacommons.org/280929517

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	The invention is more particularly adapted to lenses in which the substrate is formed by an allyl-diglycol carbonate polymer, this compound being marketed by the P.P.G. Company under the commercial designation CR 39.
http://www.w3.org/ns/prov#wasQuotedFrom	google.ca