PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • A deflecting tool particularly designed for use in directionally drilling soft formations and adapted to be connected to the lower portion of a drill stem and lowered in a well bore comprising an elongated tubular member having a longitudinal passage therethrough from its lower end to its upper end through which fluid under pressure may pass, a drilling bit secured to the lower end of said tubular
http://www.w3.org/ns/prov#wasQuotedFrom
  • google.com