Outcrop and capping characteristics of the supergene sulfide enrichment at North Silver Bell, Pima County, Arizona, in Pierce, F.W., and Bolm, J.G., eds., Porphyry copper deposits of the American Cordillera

Lopez, J.A., and Titley, S.R., 1995, Outcrop and capping characteristics of the supergene sulfide enrichment at North Silver Bell, Pima County, Arizona, in Pierce, F.W., and Bolm, J.G., eds., Porphyry copper deposits of the American Cordillera: Arizona Geological Society Digest 20, p. 424-435.