About: http://webisa.webdatacommons.org/1198608

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	As for the checking, it is a standard way to check for DOM, excluding Opera 6 and other browsers that claim to understand DOM but implement it flakily.
http://www.w3.org/ns/prov#wasQuotedFrom	alistapart.com