SP-01 The Governor’s First Conference on Environmental Geology: Proceedings SP-01 The Governor’s First Conference on Environmental Geology: Proceedings, 1969
MIN-1965-01 Compilation of Colorado Bureau of Mines Annual Reports 1896-1965 (1964 cover example) MIN-1965-01 Compilation of Colorado Bureau of Mines Annual Reports 1896-1965
MI-06 Chemical Refining Study of Base and Precious Metal Ore in Colorado MI-06 Chemical Refining Study of Base and Precious Metal Ore in Colorado