1. Abolins, J. A. and Rice, W. L.: 1987, in C. J. Londsdale (ed.),Star Formation in Galaxies, NASA Conference Publ. 2466.
2. Arp, H.: 1965,Science 148, 363.
3. Arp, H.: 1968a,Sky Telesc. 35, (No. 1), 11.
4. Arp, H.: 1968b,Astron. Zh. 45, 904.
5. Arp, H.: 1985,Astron. J. 90, 1012.