I. Chilingarian, O. Sil'Chenko, V. Afanasiev e P. Prugniel, Low Luminosity Early-type Galaxies in the NGC 128 Group, a cura di J. H. Knapen, T. J. Mahoney e A. Vazdekis, Proceedings of the conference held 23-27 April, 2007 at Santiago del Teide, Tenerife, Spain, Pathways Through an Eclectic Universe ASP Conference Series, vol. 390, San Francisco, Astronomical Society of the Pacific, giugno 2008, p. 296, Bibcode:2008ASPC..390..296C, arXiv:0711.2100.
I. Chilingarian, O. Sil'Chenko, V. Afanasiev e P. Prugniel, Low Luminosity Early-type Galaxies in the NGC 128 Group, a cura di J. H. Knapen, T. J. Mahoney e A. Vazdekis, Proceedings of the conference held 23-27 April, 2007 at Santiago del Teide, Tenerife, Spain, Pathways Through an Eclectic Universe ASP Conference Series, vol. 390, San Francisco, Astronomical Society of the Pacific, giugno 2008, p. 296, Bibcode:2008ASPC..390..296C, arXiv:0711.2100.
A.M. Garcia, General study of group membership. II - Determination of nearby groups, in Astronomy and Astrophysics Supplement Series, 100 #1, luglio 1993, p. 47-90, Bibcode:1993A&AS..100...47G.