About: http://webisa.webdatacommons.org/17779352

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	For reasons out of the scope of this question and answer, such a query as I highlighted above is not easily optimised using indexes.
http://www.w3.org/ns/prov#wasQuotedFrom	stackoverflow.com