About: http://webisa.webdatacommons.org/391292781

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	If you want to get a bit more advanced you can always go to sendmail, but considering your requirements postfix is a perfect fit.
http://www.w3.org/ns/prov#wasQuotedFrom	serverfault.com