PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Those unmanned test flights used a free-return trajectory ??? the same sort of trajectory famously used by Apollo 13.
http://www.w3.org/ns/prov#wasQuotedFrom
  • citizensinspace.org