About: http://webisa.webdatacommons.org/86436753

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	This forces the quadrilateral to have two pairs of parallel sides that are orthogonal to each other, i.e. the quadrilateral became a rectangle.
http://www.w3.org/ns/prov#wasQuotedFrom	stackexchange.com