Coal resource classification system of the U.S. Geological Survey
By: by Gordon H. Wood, Jr. ... [et al.].
Contributors: Wood, Gordon H. 1919-; Geological Survey (U.S.)
Series: Geological Survey circular -- 891.
Publisher: U.S. Dept. of the Interior, Geological Survey; Distribution Branch, Text Products Section, U.S. Geological Survey
Published: 1983
Place of publication: [Reston, Va.?]; Alexandria, VA
Language: eng
Number of pages: 65
Subjects: Geological Survey (U.S.); Coal mines and mining -- United States.
Notes: Bibliography: p. 64-65.

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