About: http://webisa.webdatacommons.org/121687929

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	2) return false if there are no children; and (3) return false if there is a child other than a first child.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com