PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Some time ago, in an article I wrote, there was a question that listed the birth date of a child, but had no actual marriage date for the parents.
http://www.w3.org/ns/prov#wasQuotedFrom
  • genealogy.com