APA (7th ed.) Citation

United States. Department of State. (1919). Use of cipher code. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Department of State. Use of Cipher Code. Washington: U.S. GPO, 1919.

MLA (9th ed.) Citation

United States. Department of State. Use of Cipher Code. U.S. GPO, 1919.

Warning: These citations may not always be 100% accurate.