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O'Meara, Stephen James (2007-04-12). “The hidden treasures”. Deep-Sky Companions: Hidden Treasures. Cambridge: Cambridge University Press. p. 457. doi:10.1017/cbo9780511536472. ISBN978-0-511-53647-2
Duncan, J. C. (1920). “Bright nebulae and star clusters in Sagittarius and Scutum photographed with the 60-inch reflector.”. The Astrophysical Journal51: 4-12. Bibcode: 1920ApJ....51....4D. doi:10.1086/142519. ISSN0004-637X.
Duncan, J. C. (1920). “Bright nebulae and star clusters in Sagittarius and Scutum photographed with the 60-inch reflector.”. The Astrophysical Journal51: 4-12. Bibcode: 1920ApJ....51....4D. doi:10.1086/142519. ISSN0004-637X.
worldcat.org
Condos; Theony (1997). Star myths of the Greeks and Romans : a sourcebook containing the Constellations of Pseudo-Eratosthenes and the Poetic astronomy of Hyginus. Grand Rapids, MI, U.S.A.: Phanes Press. pp. 129-132. ISBN978-1-60925-678-4. OCLC840823460
Hard, Robin (2015-08-01). “18-19. OPHIUCHUS, THE SERPENT-BEAERER, and THE SERPENT”. Constellation Myths: with Aratus's Phaenomena. Oxford Worlds Classics. Oxford University Press. pp. 59-64. ISBN978-0-19871-698-3. OCLC1026890396
