"How mine workers can help to prevent mne explosions."; "Harrington, D. (Daniel), 1878-"; "Coal mine accidents--United States.", "Mine explosions--United States.", "Mine fires--United States."; "Harrington, D. (Daniel), 1878-"; "1940"; "

Serial issue. Issued as: United States. Bureau of Mines. Information circular, 7138 (1940:Nov.).

"; ""; "P19472"; "pec"; "Coal mine accidents--United States.", "Mine fires--United States.", "Mine explosions--United States."; "14256"; .