PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Though galaxy clusters as massive are found in the nearby universe, such as the so-called Bullet Cluster, nothing like this has ever been seen to exist so far back in time, when the universe was roughly half of its current age of 13.8 billion years.
http://www.w3.org/ns/prov#wasQuotedFrom
  • sciencedaily.com