About: http://webisa.webdatacommons.org/80653447

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	Other gases, such as nitrogen, carbon dioxide, methane, ethane and the like may also be utilized, but are generally not economical.
http://www.w3.org/ns/prov#wasQuotedFrom	google.com