| Reference | {Commodity:: MINERAL RESOURCES DATA SYSTEM, RECORD # ISM0150, PP. 1-2}{Commodity:: (NOV. 22, 1991).}{Commodity:: NATIONAL MATERIALS ADVISORY BOARD, MANGANESE}{Commodity:: RESERVES AND RESOURCES OF THE WORLD AND THEIR INDUSTRIAL}{Commodity:: IMPLICATIONS: NMAB-374, NATIONAL ACADEMY OF SCIENCES,}{Commodity:: WASHINGTON, DC. P. 123-25 (1981).} |