National Minerals Act of 1949: Hearings Before a Subcommittee on Mines and Mining of the Committee on Public Lands, House of Representatives, Eighty-first Congress, First Session on H.R. 976, H.R. 2031, H.R. 2406, and Related Bills, to Stimulate the Exploration, Production, and Conservation of Strategic and Critical Ores, Metals, and Minerals and for the Establishment Within the Department of the Interior of a Mine Incentive Payments Division, and for Other Purposes, February 16, 17, 18, and 21, March 9 and 10, April 7, 1949