PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • As optical communication systems employed in the case of communicating using coherent light such as a laser, a beam guide system having focussing elements such as optical lenses or reflectors periodically disposed in space, a space transmission system, and a system using an optical fiber made of a light-transparent material such as, for example, glass, plastics, etc., are known.
http://www.w3.org/ns/prov#wasQuotedFrom
  • google.com