PGC 033991 = VV 237a = NGC 3561B in RC2.
= NGC 3561B
Listed in RC1 as A1108B.
Part of Arp 105 = VV 237 with Components A and C.
= NGC 3561A
Part of Zwicky connected multiple system.
Separation of [RC1] A1108A from [RC1] A1108B: 55.6 arcsec.
Separation of [RC1] A1108B from [RC1] A1108C: 30.5 arcsec.
Erg. d. Exakt. Naturwiss., XXIX, 344, 1956.
Magnitude, Systemic Velocity, and Mass:
A.J., 133, 794, 1961.