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Coal reserves of Washington
Beikman, Helen M., (1961)
Coal reserves of Pennsylvania : total, recoverable, and strippable (January 1, 1970)
Edmunds, William E., (1972)
Economics and coal resourse appraisal : Strippable coal in the Illinois basin
Attanasi, E. D., (1981)
Missouri minerals : resources, production, and forecasts
Wharton, Heyward M., (1969)