APA (7th ed.) Citation

United States Naval Observatory. Nautical Almanac Office. (1938). The American Ephemeris and Nautical Almanac, For the Year 1940. [s.n.].

Chicago Style (17th ed.) Citation

United States Naval Observatory. Nautical Almanac Office. The American Ephemeris and Nautical Almanac, For the Year 1940. [Washington]: [s.n.], 1938.

MLA (9th ed.) Citation

United States Naval Observatory. Nautical Almanac Office. The American Ephemeris and Nautical Almanac, For the Year 1940. [s.n.], 1938.