A4. THE NGC 1023 GROUP
This group is very well defined. All the galaxies classified as
certain members are found within 6^deg^ of NGC 1023 and have very
similar systemic velocities. NGC 855, for which an SBF distance exists,
is located 12^deg^ away from NGC 1023, and 6^deg^ from NGC 925, which
is itself at the outer boundary of the core region. The systemic
velocity of NGC 855 is only 50 km s^-1^ lower than for NGC 1023. Because
no other obvious member of the group is located outside a 6^deg^ radius
from NGC 1023, we classify NGC 855 as a probable rather than a certain
member. Unfortunately, NGC 855 is not included in either the N93 or the
T88 catalogs. T88 classifies all of our certain members of the
NGC 1023 group as belonging to the Triangulum spur (cloud 17), group -1.
NGC 891 is further placed in the first-level association +1.