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Annual report of research and technologic work on coal, fiscal year 1940
Annual report of research and technologic work on coal, fiscal year 1939
Annual report of research and technologic work on coal :fiscal year 1944
Inspection standards for bituminous-coal and lignite mines :revised July 1945.
Annual report of research and technologic work on coal :fiscal year 1945
Wash and change houses at American mines
Annual report of research and technologic work on coal :fiscal year 1947
Annual report of research and technologic work on coal :fiscal year 1948