About: http://webisa.webdatacommons.org/351877727

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	I would say by evidence other than their statements that can be used for corroboration.
http://www.w3.org/ns/prov#wasQuotedFrom	websleuths.com