References
WALENGA, KAREN, 1987, NEW OPERATION TO DOUBLE ARIZONA GOLD PRODUCTION: SOUTHWESTERN PAY DIRT, NO. 581, P. 4A-5A.WALENGA, KAREN, 1988, CYPRUS STARTS WORK ON UNDERGROUND MINE AT COPPERSTONE: SOUTHWESTERN PAYDIRT, NO. 592, P. 5A.SPENCER, J.E., DUNCAN, J.T., AND BURTON, W.D., 1988, THE COPPERSTONE MINE: ARIZONA'S NEW GOLD PRODUCER: ARIZONA BUREAU OF GEOLOGY AND MINERAL TECHNOLOGY FIELDNOTES, V. 18, NO. 2, P. 1-3.PETERSON, E.K., AND DUPREE, J.A., 1993, PRELIMINARY INVESTIGATION OF BULK MINABLE GOLD DEPOSITS, COLORADO RIVER INDIAN RESERVATION, ARIZONA AND CALIFORNIA, IN MANYDEEDS, S.A., AND SMITH, B.D., EDS., MINERAL FRONTIERS ON INDIAN LANDS: BUREAU OF INDIAN AFFAIRS DIVISION OF ENERGY AND MINERAL RESOURCES, P. 35-42.NIEMUTH, N.J., 1987, ARIZONA MINERAL DEVELOPMENT 1984-1986: ARIZONA DEPARTMENT OF MINES AND MINERAL RESOURCES DIRECTORY 29, 46 P.SAWYER, M.B., GURMENDI, A.C., DALEY, M.R., AND HOWELL, S.B., 1992, PRINCIPAL DEPOSITS OF STRATEGIC AND CRITICAL MINERALS IN ARIZONA: UNITED STATS BUREAU OF MINES SPECIAL PUBLICATION, 334 P.MINERAL TODAY, 1/90, P. 26.CIMRIWALENGA, 1987, P. 4A; SAWYER AND OTHERS, 1992; MINERAL TODAY, 1990.WALENGA, 1988, P. 5A; NIEMUTH, 1987.