Cobre Ridge

Knight, L.H., Jr., 1970, Structure and mineralization of the Oro Blanco mining district, Santa Cruz County, Arizona: Tucson, University of Arizona, Ph.D. dissertation, 172 p., 7 sheets, scales 1:1,200, 1:6,000, 1:16,000, 1:24,000, 1:60,000, 1:62,500, and 1:358,000.

Keyes, Charles, 1923, Tres Amigos gold veins of Arizona: Pan-American Geologist, v. 39, no. 2, p. 159-160.

Keith, W.J., and Theodore, T.G., 1975, Reconnaissance geologic map of the Arivaca quadrangle, Arizona: U.S. Geological Survey Miscellaneous Field Studies Map MF-678, 1 sheet, scale 1:63,360.

Keith, Stanton B., 1975, Index of mining properties in Santa Cruz County, Arizona: Arizona Bureau of Mines Bulletin 191, 94 p. [reprinted 1990, Arizona Geological Survey].

Johnson, M.G., 1972, Placer gold deposits of Arizona: U.S. Geological Survey Bulletin 1355, 103 p., 1 sheet.

Arizona Geothermal Commercialization Team, 1980, Geothermal development plan: Cochise and Santa Cruz Counties: Arizona Bureau of Geology and Mineral Technology Open-File Report 80-09, 40 p.

Girand, J.B., 1933, Centrifugal concentration of placer gravel: Engineering and Mining Journal, v. 134, no. 3, p. 110-111.

Farnham, L.L., Stewart, L.A., and DeLong, C.W., 1961, Manganese deposits of eastern Arizona: U.S. Bureau of Mines Information Circular I.C. 7990, 178 p.

Drewes, H.D., 1980, Tectonic map of southeast Arizona: U.S. Geological Survey Miscellaneous Investigations Series Map I-1109, 2 sheets, scale 1:125,000.

Drewes, H.D., 1976, Laramide tectonics from Paradise to Hells Gate, southeastern Arizona, in Wilt, J.C., and Jenney, J.P., eds., Tectonic digest: Arizona Geological Society Digest, v. 10, p. 151-167.