About: http://webisa.webdatacommons.org/109885253

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	U.S. Pat. No. 3,141,440 shows an impact-recording instrument that uses a set of balls placed around the periphery of a softer material such as lead or aluminum.
http://www.w3.org/ns/prov#wasQuotedFrom	google.es