APA (7th ed.) Citation

Cash, F. E., & Humphrey, H. B. (1931). Lost-time accidents in some Alabama coal and iron mines during 1930. [publisher not identified].

Chicago Style (17th ed.) Citation

Cash, Frank E., and H. B. Humphrey. Lost-time Accidents in Some Alabama Coal and Iron Mines During 1930. Washington, D.C.: [publisher not identified], 1931.

MLA (9th ed.) Citation

Cash, Frank E., and H. B. Humphrey. Lost-time Accidents in Some Alabama Coal and Iron Mines During 1930. [publisher not identified], 1931.