About: http://webisa.webdatacommons.org/390740973

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	Yes, you can block PDF files on your SMTP... but then users will e.g. use hotmail account to upload and send out PDF files.
http://www.w3.org/ns/prov#wasQuotedFrom	derkeiler.com