"State regulations pertaining to the use of internal-combustion engines in coal and metal mines and in tunnels."; "Gleim, E. J. (Ernest J.)", "Ilsley, L. C. (Lee Clyde), 1880-"; "Tunnels--Safety measures.", "Internal combustion engines--Safety measures.", "Mine safety--United States."; "Gleim, E. J. (Ernest J.)", "Ilsley, L. C. (Lee Clyde), 1880-"; "1938"; "

Serial issue. Issued as: United States. Bureau of Mines. Information circular, 7019 (1938:June).

"; ""; "P19468"; "pec"; "Mine safety--United States.", "Tunnels--Safety measures.", "Internal combustion engines--Safety measures."; "14256"; .