Não informado. (1964). Commodity Data Summaries. U.S. Department of the Interior, Bureau of Mines.
Cita Chicago Style (17a ed.)Não informado. Commodity Data Summaries. Washington: U.S. Department of the Interior, Bureau of Mines, 1964.
Cita MLA (8a ed.)Não informado. Commodity Data Summaries. U.S. Department of the Interior, Bureau of Mines, 1964.
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