U.S. Coast and Geodetic Survey. (1922). Magnetic declination in U.S. for Jan. 1, 1920. GPO.
Chicago Style (17th ed.) CitationU.S. Coast and Geodetic Survey. Magnetic Declination in U.S. for Jan. 1, 1920. [Washington]: GPO, 1922.
MLA (9th ed.) CitationU.S. Coast and Geodetic Survey. Magnetic Declination in U.S. for Jan. 1, 1920. GPO, 1922.
Warning: These citations may not always be 100% accurate.