↑G. de Vaucouleurs et al., Second Reference Catalogue of Bright Galaxies, 1976
↑Sky Catalogue 2000.0, Volume 2: double stars, variable stars and nonstellar objects (edited by Alan Hirshfeld and Roger W. Sinnott), page xlix: Glossary of selected astronomical names
↑Hugh C. Maddocks: Deep-Sky Name Index 2000.0 (Foxon-Maddocks Associates, 1991)
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