PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • The method which Herr RUHMER adopts is essentially optical, and consists in the action upon an electro-optically sensitive body, or electric eye, of a beam of electric or other powerful light projected from the sending to the transmitting station.
http://www.w3.org/ns/prov#wasQuotedFrom
  • earlyradiohistory.us