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de Vaucouleurs, G.; Oemler, Augustus, Jr.; Butcher, Harvey R.; Gunn, James E. (1955). “Studies of Magellanic Clouds. I. Dimensions and structure of the Large Cloud”. The Astronomical Journal. 160: 126–140. Bibcode:1955AJ.....60..126D. doi:10.1086/107173.
Dressler, A.; Oemler, Jr., A.; Butcher, H. R.; Gunn, J. E. (tháng 7 năm 1994). “The morphology of distant cluster galaxies. 1: HST observations of CL 0939+4713”. The Astrophysical Journal. 430 (1): 107–120. Bibcode:1994ApJ...430..107D. doi:10.1086/174386.