1. Aaronson, M.: 1986, in D. Kunth, D. Thaun, and J. Van (eds.),Star Forming Dwarf Galaxies and Related Objects, Editions Frontiers, Gif-sur-Yvette, p. 331.
2. Aaronson, M. and Mould, J.: 1985,Astrophys. J. 290, 191.
3. Aaronson, M. and Olszewski, E.: 1987, in G. R. Knapp (ed.), ?Dark Matter in the Universe?,IAU Symp.117, 153.
4. Binggeli, B., Sandage, A., and Tammann, G. A.: 1985,Astron. J. 90, 1681).
5. Bothun, G. D.: 1982.Astrophys. J. Suppl. 50, 39.