Aiken, D.M., and West, R.J., 1978, Some geologic aspects of the Sierrita-Esperanza copper-molybdenum deposit, Pima County, Arizona, in Jenney, J.P., and Hauck, H.R., eds., Proceedings of the Porphyry Copper Symposium, Tucson, Ariz., March 18-20, 1976: Arizona Geological Society Digest, v. 11, p. 117-128.