APA (7th ed.) Citation

Crawford, F. S. (1931). Safety standards and safety suggestions at iron mines in Lake Superior region. [publisher not identified].

Chicago Style (17th ed.) Citation

Crawford, F. Stuart. Safety Standards and Safety Suggestions at Iron Mines in Lake Superior Region. Washington, D.C.: [publisher not identified], 1931.

MLA (9th ed.) Citation

Crawford, F. Stuart. Safety Standards and Safety Suggestions at Iron Mines in Lake Superior Region. [publisher not identified], 1931.