<http://webisa.webdatacommons.org/prov/178878233>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/248279713> .
<http://webisa.webdatacommons.org/248279713>	<http://www.w3.org/1999/02/22-rdf-syntax-ns#type>	<http://www.w3.org/ns/prov#Entity> .
<http://webisa.webdatacommons.org/prov/381573727>	<http://www.w3.org/ns/prov#wasDerivedFrom>	<http://webisa.webdatacommons.org/248279713> .
<http://webisa.webdatacommons.org/248279713>	<http://www.w3.org/ns/prov#value>	"drilling and production equipment and services, environmental risks, drilling and other operating risks, regulatory changes, the uncertainty inherent in estimating proved oil and natural gas reserves" .
<http://webisa.webdatacommons.org/248279713>	<http://www.w3.org/ns/prov#wasQuotedFrom>	<sec.gov> .