About: http://webisa.webdatacommons.org/330649210

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	Perhaps the conversion bit can be made through a virtual function, but the validation part would not really be plausible, I think, since you want to hand off the validation to the class and have many different types of validation.
http://www.w3.org/ns/prov#wasQuotedFrom	cprogramming.com