APA (7th ed.) Citation

Gaines, H. F. (1939). Elementary cryptanalysis: A study of ciphers and their solution. American Photographic Publishing co..

Chicago Style (17th ed.) Citation

Gaines, Helen Fouché. Elementary Cryptanalysis: A Study of Ciphers and Their Solution. Boston: American Photographic Publishing co., 1939.

MLA (9th ed.) Citation

Gaines, Helen Fouché. Elementary Cryptanalysis: A Study of Ciphers and Their Solution. American Photographic Publishing co., 1939.