Não informado. (1855). Annals of the Astronomical Observatory of Harvard College. Harvard College Observatory.
Chicago-referens (17:e uppl.)Não informado. Annals of the Astronomical Observatory of Harvard College. Cambridge, Mass: Harvard College Observatory, 1855.
MLA-referens (8:e uppl.)Não informado. Annals of the Astronomical Observatory of Harvard College. Harvard College Observatory, 1855.
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