Extension of Bituminous coal act of 1937, Hearings before the Committee on ways and means, House of representatives, Seventy-seventh Congress, first session, on H.J. Res. 101, a joint resolution extending the provisions of the Bituminous coal act of 1937 for a period of two years. Revised. March 11, 12, 13, 14, 15, 17, 18, and 19, 1941