Louis; Berman. The spectroscopic orbit of the fainter component in the system [xi] Ursae Majoris (англ.) // Lick Observatory Bulletin No. 432 : journal. — 1931. — Vol. 15. — P. 109. — doi:10.5479/ADS/bib/1931LicOB.15.109B. — Bibcode: 1931LicOB..15..109B.
doi.org
Mason, Brian D.; McAlister, Harold A.; Hartkopf, William I.; Shara, M. M.; Shara, M. M. (January 1995), "Binary star orbits from speckle interferometry. 7: The multiple system XI Ursae Majoris", The Astronomical Journal (англ.), 109 (1669): 332–340, Bibcode:1995AJ....109..332M, doi:10.1086/117277
Louis; Berman. The spectroscopic orbit of the fainter component in the system [xi] Ursae Majoris (англ.) // Lick Observatory Bulletin No. 432 : journal. — 1931. — Vol. 15. — P. 109. — doi:10.5479/ADS/bib/1931LicOB.15.109B. — Bibcode: 1931LicOB..15..109B.
ui.adsabs.harvard.edu
Mason, Brian D.; McAlister, Harold A.; Hartkopf, William I.; Shara, M. M.; Shara, M. M. (January 1995), "Binary star orbits from speckle interferometry. 7: The multiple system XI Ursae Majoris", The Astronomical Journal (англ.), 109 (1669): 332–340, Bibcode:1995AJ....109..332M, doi:10.1086/117277