About: http://webisa.webdatacommons.org/425355421

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	A viewer such as Adobe Reader or Xpdf is needed to view a document encoded in PDF. Various PDF viewers are widely deployed on the Internet.
http://www.w3.org/ns/prov#wasQuotedFrom	cert.org