<http://webisa.webdatacommons.org/prov/417387919>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/342956210> .
<http://webisa.webdatacommons.org/prov/208563328>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/342956210> .
<http://webisa.webdatacommons.org/342956210>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/342956210>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<iwar.org.uk> .
<http://webisa.webdatacommons.org/342956210>	<http://www.w3.org/ns/prov#value>	"Although it is generally not necessary to install special-purpose air purifiers for the OA System, cutting down or eliminating such contaminants as smoke and dust can only help the OA System and its media." .