PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • A system and method according to the present invention for screening out unsolicited commercial messages comprises the steps of receiving a message from a sender, sending a challenge back to the sender, receiving a response to the challenge, and determining if the response is a proper response.
http://www.w3.org/ns/prov#wasQuotedFrom
  • google.fr