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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	Refraction studies, on the other hand, are capable of being used in shallower ground, but they have some limitations, such as difficulty when surveying involves materials of high density overlayed on materials of lower density.
http://www.w3.org/ns/prov#wasQuotedFrom	wisegeek.com