PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Propane combustion is much cleaner than gasoline and other liquid hydrocarbons, though not quite as clean as natural gas combustion.
http://www.w3.org/ns/prov#wasQuotedFrom
  • wisegeek.org