About: http://webisa.webdatacommons.org/101652543

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	Your option is a good one but I marked mine as the answer because it was simpler. (It was a one liner) Yours is probably better memory wise though, probably a little less top heavy.
http://www.w3.org/ns/prov#wasQuotedFrom	superuser.com