PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Currently, email systems treat each email as a separate entity, indicating by a ???RE??? or a ???FWD??? preceding the subject that the email is a reply or a forwarded email, and there is no way to automatically relate one email to another.
http://www.w3.org/ns/prov#wasQuotedFrom
  • google.com