About: http://webisa.webdatacommons.org/421975259

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	In fact, the three kinds of signals thereof need not always be outputted and, moreover, more than three kinds of signals can be outputted.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com