Ingersoll, G. E. (1933). Small scale methods of placer mining and placer mining districts of Washington and Oregon. State college of Washington.
Cita Chicago Style (17a ed.)Ingersoll, Guy Ernest. Small Scale Methods of Placer Mining and Placer Mining Districts of Washington and Oregon. [Pullman: State college of Washington, 1933.
Cita MLA (8a ed.)Ingersoll, Guy Ernest. Small Scale Methods of Placer Mining and Placer Mining Districts of Washington and Oregon. State college of Washington, 1933.
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