About: http://webisa.webdatacommons.org/447050465

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	Congress passed the Clean Air Act in the 1970s, when the air pollutants of concern were substances such as lead or particulate matter.
http://www.w3.org/ns/prov#wasQuotedFrom	stopglobalwarming.org