APA (7th ed.) Citation

United States. Weather Bureau. (1931). Weather code, 1931. GPO.

Chicago Style (17th ed.) Citation

United States. Weather Bureau. Weather Code, 1931. [Washington]: GPO, 1931.

MLA (9th ed.) Citation

United States. Weather Bureau. Weather Code, 1931. GPO, 1931.

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