PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Massive investment in the production of shale gas has driven the U.S. supply boom, thanks in large part to new technologies such as hydraulic fracking, which has made the extraction of oil and gas from shale rock commercially viable.
http://www.w3.org/ns/prov#wasQuotedFrom
  • cnn.com