http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Assessment of the natural gas resource base of the United States
Office of Policy, Planning, and Analysis.
"Originally prepared for U.S. Department of Energy, Office of Policy, Planning & Analysis and released as DOE/W/31109-H1."
Includes bibliographical references (pages 25-27).
Report of investigations (University of Texas at Austin. Bureau of Economic Geology) ; no. 179