| Reference | {Deposit:: SCOTT, D.C., 1983, MINERAL INVESTIGATION OF THE WEST NEEDLE WILDERNESS STUDY AREA AND THE BLM WEST NEEDLE CONTIGUOUS WILDERNESS STUDY AREA, LA PLATA AND SAN JUAN COUNTIES, COLORADO: USBM MLA 35-83.}{Deposit:: BARKER, FRED, 1969, PRECAMBRIAN GEOLOGY OF THE NEEDLE MOUNTAINS, SOUTHWESTERN COLORADO: USGS PROF. PAPER 644-A.}{Deposit:: CROSS, WHITMAN, AND HOLE, A.D., 1910, DESCRIPTION OF THE ENGINEER MOUNTAIN QUADRANGLE: USGS FOLIO 171.}{Deposit:: HENDERSON, C.W., 1926, MINING IN COLORADO, A HISTORY OF DISCOVERY, DEVELOPMENT, AND PRODUCTION: USGS PROF. PAPER 138. P. 177-178.}{Deposit:: BURCHARD, H.C., 1884, COLORADO--LA PLATA COUNTY, IN REPORT OF THE DIRECTOR OF THE MINT, UPON THE PRODUCTION OF PRECIOUS METALS IN THE UNITED STATES DURING THE CALENDAR YEAR 1883: GPO, P. 368-376.}{Deposit:: BLM MINERAL SURVEYS MS 1778, 1779, 20762.}{Deposit:: STEVEN, T.A., AND OTHERS, 1974, GEOLOGIC MAP OF THE DURANGO QUADRANGLE, SOUTHWESTERN COLORADO: USGS MAP I-764.}{Deposit:: COLORADO DIV. MINES INF. REPT.} |