PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Sandage believes that some kinds of supernova can serve as standard candles of known intrinsic brightness, much as Cepheids do; he argues that the Hubble constant is around 50 and that the universe is a comfortable 15 to 20 billion years old.
http://www.w3.org/ns/prov#wasQuotedFrom
  • discovermagazine.com