About: http://webisa.webdatacommons.org/325045596

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	@Constraints.Required is a validation, which ensures that the value not null.
http://www.w3.org/ns/prov#wasQuotedFrom	stackoverflow.com