About: http://webisa.webdatacommons.org/109412595

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 practice various types of head may be used, in particular heads using balls, vacuum pick-ups, cones, clamps, etc
http://www.w3.org/ns/prov#wasQuotedFrom	freepatentsonline.com