Alpamina

AIRGRAM FROM U.S. EMBASSY IN LIMA, DEC. 21, 1978FREEMAN PUBLICATIONS, INC., SAN FRANCISCO, 1979, P. 152.RIO TINTO ZINC MINING ANALYSIS SYSTEM. LEAD AND ZINC MINESOF THE WORLD (ZINC). MARCH 25, 1975, P. 22.OF THE WORLD (LEAD). MARCH 25, 1975, P. 21.ENGINEERING AND MINING JOURNAL INTERNATIONAL DIRECTORY OFMINING AND MINERAL PROCESSING OPERATIONS. PERU. MCGRAW-HILL, INC., NEW YORK, 1978, P. 328.RIO TINTO ZINC MINING COST ANALYSIS SYSTEM. PERFORMANCEANALYSIS. FEBRUARY 25, 1975, P. 264, 292, 411.