ALMANAC. (1991). Almanac for computers 1991. Nautical Almanac Office.
芝加哥风格引文ALMANAC. Almanac for Computers 1991. Washington: Nautical Almanac Office, 1991.
MLA引文ALMANAC. Almanac for Computers 1991. Nautical Almanac Office, 1991.
警告：这些引文格式不一定是100％准确.