About: http://webisa.webdatacommons.org/60750455

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	Apparently, PDF is an open standard, that can be implemented by anyone in any piece of software.
http://www.w3.org/ns/prov#wasQuotedFrom	superuser.com