U.S. Geological Survey National Mineral Resource Assessment Team. (1999). 1998 assessment of undiscovered deposits of gold, silver, copper, lead, and zinc in the United States. U.S. G.P.O. Free on application to U.S. Geological Survey, Information Services.
Chicago Style (17th ed.) CitationU.S. Geological Survey National Mineral Resource Assessment Team. 1998 Assessment of Undiscovered Deposits of Gold, Silver, Copper, Lead, and Zinc in the United States. Washington, Denver, CO: U.S. G.P.O. Free on application to U.S. Geological Survey, Information Services, 1999.
MLA (9th ed.) CitationU.S. Geological Survey National Mineral Resource Assessment Team. 1998 Assessment of Undiscovered Deposits of Gold, Silver, Copper, Lead, and Zinc in the United States. U.S. G.P.O. Free on application to U.S. Geological Survey, Information Services, 1999.