About: http://webisa.webdatacommons.org/51398697

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 signals have at least an audio component that represents sounds picked up from a subscriber microphone or DTMF (Dual Tone Multiple Frequency) tones produced on a handset, however other types of signals can also be supported.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com