Chihuahua

MINING ANALYSIS SYSTEM ECONOMIC PLANING RTZ, 1975, P. 192.MINING ANALYSIS SYSTEM ECOMOMIC PLANING RTZ, 1975, P. 170.STAFF, ENGINEERING AND MINING JOURNAL INTERNATIONALDIRECTORY OF MINING AND MINERAL PROCESSING OPERATIONS,NEW YORK, MCGRAW-HILL, 1978, P. 314.NEW YORK, MCGRAW-HILL, 1976, P. 255.THE WORLD-WIDE DIRECTORY OF MINING AND MINERAL PROCESSINGOPERATIONS, 1976-77, P. 116.