PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Each radioactive element, including strontium, constantly gives off radiation, and this process changes it into an isotope of another element or a different isotope of the same element.
http://www.w3.org/ns/prov#wasQuotedFrom
  • eoearth.org