About: http://webisa.webdatacommons.org/95029479

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	There, the sites I stumble have the SU prefix ??? and as you say ??? with no way to remove the prefix except to just cut it out of the URL.
http://www.w3.org/ns/prov#wasQuotedFrom	onecoolsitebloggingtips.com