About: http://webisa.webdatacommons.org/321662408

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	BACKGROUND OF THE INVENTION Recording instruments have previously been constructed to record electrical quantities such as voltage and current.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com