Comment on SN.... : The position of this SN is 0".7 west and 2".4 south of SN 1996bw ( it was pointed out in IAU Circular 6551, 1997 ). So the position of SN 1997W assumed to be 20".4 west and 5".7 south of the center of the host galaxy.
Comment on Gal... : N 664
Host Galaxy information (for SNe discovered since January 2015):