About: http://webisa.webdatacommons.org/110337419

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 Clean Air Act enacted in the U.S. in 1970 has been modified several times, including amendments implemented in 1994 that regulated emissions, especially from coal-burning power plants.
http://www.w3.org/ns/prov#wasQuotedFrom	phys.org