Cita APA (7th ed.)

ALMANAC. (1991). Almanac for computers 1991. Nautical Almanac Office.

Cita Chicago (17th ed.)

ALMANAC. Almanac for Computers 1991. Washington: Nautical Almanac Office, 1991.

Cita MLA (9th ed.)

ALMANAC. Almanac for Computers 1991. Nautical Almanac Office, 1991.