About: http://webisa.webdatacommons.org/180582871

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	The key is to right-click on each join field, such as Elevation, to define the Merge Rule.
http://www.w3.org/ns/prov#wasQuotedFrom	stackexchange.com