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Summarized data of zinc production : showing the relation of production in the United States to that of the world
Pehrson, Elmer W., (1929)
Value of 1928 mine production of gold, silver, copper, lead, zinc, and iron ore of the United States by states and districts yielding $ 100 000 or more
Pehrson, Elmer W., (1928)
Minerals in national and international affairs
Pehrson, Elmer W., (1959)