PropertyValue
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.w3.org/ns/prov#value
  • By the early 20th century, tens of thousands of workers were dying every year on the railroads, in factories, and especially in coal mines, including many boys and adolescents (see Primary Source Jokerville Coal Mine Explosion [1844] and Primary Source Breaker Boys at Work [1911]).
http://www.w3.org/ns/prov#wasQuotedFrom
  • teachinghistory.org