About: http://webisa.webdatacommons.org/184234315

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	Alternatively to effect a reference pulse, other means can be employed, such as a lamp and photocell arrangement or the like.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com