<http://webisa.webdatacommons.org/93856861>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/prov/372048826>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/93856861> .
<http://webisa.webdatacommons.org/93856861>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<credoreference.com> .
<http://webisa.webdatacommons.org/93856861>	<http://www.w3.org/ns/prov#value>	"An assembly of valves, tees, crosses, and other things at the wellhead, used to control oil or gas production and to give access to the well tubing.Citation" .