About: http://webisa.webdatacommons.org/5510135

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	To prove that the set is closed: since we have finite points of $y$ that satisfies the condition, the our set is a set of points, which implies it is closed.
http://www.w3.org/ns/prov#wasQuotedFrom	stackexchange.com