C.A. Hummel, et al.. The spectroscopic binary eta Andromedae: Determination of the orbit by optical interferometry. „Astronomical Journal”. 106 (6), s. 2486–2492, grudzień 1993. DOI: 10.1086/116816. Bibcode: 1993AJ....106.2486H.
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C.A. Hummel, et al.. The spectroscopic binary eta Andromedae: Determination of the orbit by optical interferometry. „Astronomical Journal”. 106 (6), s. 2486–2492, grudzień 1993. DOI: 10.1086/116816. Bibcode: 1993AJ....106.2486H.