ALMANAC. (1991). Almanac for computers 1991. Nautical Almanac Office.
Chicago-čujuhus (17. p.)ALMANAC. Almanac for Computers 1991. Washington: Nautical Almanac Office, 1991.
MLA-čujuhus (9. p.)ALMANAC. Almanac for Computers 1991. Nautical Almanac Office, 1991.
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