Author:

Ellis,M.S.;Nichols,D.J.

Year:

2002

Title:

A summary of the U.S. Geological Survey 1999 Resource Assessment of selected coal zones in the Northern Rocky Mountains and Great Plains Region, Wyoming, Montana, and North Dakota.

Reference:

Ellis,M.S. et al. (2002) A summary of the U.S. Geological Survey 1999 Resource Assessment of selected coal zones in the Northern Rocky Mountains and Great Plains Region, Wyoming, Montana, and North Dakota. United States Geological Survey, Bulletin # 2189 P. 1- 14

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