PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Raw natural gas contains methane, other hydrocarbons called natural gas liquids, nitrogen and impurities such as sand, water, carbon dioxide (CO2), hydrogen sulphide.
http://www.w3.org/ns/prov#wasQuotedFrom
  • wallstreetoasis.com