PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • That shale gas exists in abundance ??? in the U.S., Europe, Australia, China, South Africa, and other regions ??? is beyond question.
http://www.w3.org/ns/prov#wasQuotedFrom
  • cleantechies.com