"Some suggestions on the safe handling of electric shovel trailing cables in open-pit mines."; "Crawford, F. S."; "Mine safety.", "Electric cables.", "Mining machinery--Electric equipment.", "Coal mines and mining--Electric equipment."; "Crawford, F. S."; "1936"; "

Serial issue. Issued as: United States. Bureau of Mines. Information circular, 6922 (1936:Nov.).

"; ""; "P19466"; "pec"; "Coal mines and mining--Electric equipment.", "Electric cables.", "Mining machinery--Electric equipment.", "Mine safety."; "14256"; .