Actions for Stockpile and Accessibility of Strategic and Critical Materials to the U.S. in Time of War. Part 4, International Materials Conference [electronic resource] : hearings before the United States Senate Committee on Interior and Insular Affairs, Special Subcommittee on Minerals, Materials and Fuels Economics, Eighty-Third Congress, first session and Eighty-Third Congress, second session, on Oct. 21, 1953, Jan. 5, 13-15, 18, 1954