Landis, E. R. (1959). Coal resources of Colorado: Contributions to economic geology ; a highly detailed estimate of the reserves in coal bearing rocks, which underlie a quarter of the state. United States Government Printing Office.
Chicago-Zitierstil (17. Ausg.)Landis, Edwin R. Coal Resources of Colorado: Contributions to Economic Geology ; a Highly Detailed Estimate of the Reserves in Coal Bearing Rocks, Which Underlie a Quarter of the State. Washington: United States Government Printing Office, 1959.
MLA-Zitierstil (9. Ausg.)Landis, Edwin R. Coal Resources of Colorado: Contributions to Economic Geology ; a Highly Detailed Estimate of the Reserves in Coal Bearing Rocks, Which Underlie a Quarter of the State. United States Government Printing Office, 1959.
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