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USA | |
| Butler, B. S. (1915) Contributions to economic geology, 1913, Part I, Metals and nonmetals except fuels--Notes on the Unaweep copper district, Colorado. USGS Bulletin: 580-B |
| Minerals of Colorado 2nd ed. |
| Minerals of Colorado 2nd ed. |
| Eckel, Edwin Butt , Cobban, Robert R., Mosburg, Shirley K., Foord, Eugene E. (1997) Minerals of Colorado. Fulcrum Publishing. |