Economic Geology of the Georgetown Quadrangle (together with the Empire District), Colorado, by Josiah E. Spurr and George H. Garrey, with General Geology, by Sydney H. Ball. [U.S. Geological Survey Professional Paper 63.].

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Economic Geology of the Georgetown Quadrangle (together with the Empire District), Colorado, by Josiah E. Spurr and George H. Garrey. With General Geology, by Sydney H. Ball

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Economic Geology of the Georgetown Quadrangle (together with the Empire District) Colorado

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Economic Geology of the Georgetown Quadrangle (together with the Empire District) Colorado

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Geological Survey Professional Paper

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The Journal of the Manchester Geographical Society

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The American Journal of Science

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Bulletin

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Journal

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Geology and Ore Deposits of the Breckenridge District, Colorado

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