About: http://webisa.webdatacommons.org/444926881

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	You can first try with making the column visible and check whether you are getting value or not... i am sure that you will not get valuefor that null column value....
http://www.w3.org/ns/prov#wasQuotedFrom	nullskull.com