<http://webisa.webdatacommons.org/21825980>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/21825980>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<google.fr> .
<http://webisa.webdatacommons.org/prov/249695292>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/21825980> .
<http://webisa.webdatacommons.org/21825980>	<http://www.w3.org/ns/prov#value>	"This problem is particularly acute when the excavation is carried out by a powered excavating tool such as a back hoe mounted on an excavator vehicle." .