PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • Measuring the cost of spam, which takes into account such factors as lost productivity and wasted time, is an imprecise science, and estimates on its total toll vary: Ferris Research reckons that spam cost the United States $10 billion in 2003, while Nucleus Research pegs the U.S. cost around $87 billion.
http://www.w3.org/ns/prov#wasQuotedFrom
  • acm.org