About: http://webisa.webdatacommons.org/71961154

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	The major email providers such as Gmail and Yahoo do some sanity checks such as the following at the SMTP level to prevent spam to arrive the users' mailboxes:
http://www.w3.org/ns/prov#wasQuotedFrom	stackexchange.com