PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • In fracking, water, sand and other substances are injected into a well under high pressure in order to fracture the rock, creating fissures that help natural gas flow out.
http://www.w3.org/ns/prov#wasQuotedFrom
  • yahoo.com