APA (7th ed.) Citation

Friedman, W. F. (1977). Solving German codes in World War I: [with an added special "code problem" for the student]. Aegean Park Press.

Chicago Style (17th ed.) Citation

Friedman, William F. Solving German Codes in World War I: [with an Added Special "Code Problem" for the Student]. Laguna Hills, Calif.: Aegean Park Press, 1977.

MLA (9th ed.) Citation

Friedman, William F. Solving German Codes in World War I: [with an Added Special "Code Problem" for the Student]. Aegean Park Press, 1977.