Mining statistics 1967 RP 47 1968
Mining statistics 1966 RP 10 1968
Mining statistics 1970 RP 32 1971
Mining statistics 1971 RP 53 1972
Mining statistics 1972 RP 37 1973
Mining statistics 1973 RP 44 1974
Mining statistics 1975 RP 27 1976
Mining statistics 1976 RP 31 1977
Mining statistics 1978 RP 74 1979
Mining statistics 1979 RP 96 1980
Mining statistics 1981 RP 102 1982
Mining statistics RP 48 1984
Mining statistics 1983 RP 25 1985
