association yy = 0 zz : If zz not given, then zz is assumed to be the same as |yy| See also NBG: NBG galaxies are members of 36 clouds, 254 associations and 336 groups of two or more members.
Astrophys. J., 321, 280-304 (1987)
Nearby groups of galaxies. II. An all-sky survey within 3000 kilometers per second.
oTable 2: <NBGG xx+yy +zz> N=340
=E=Catalogue in electronic form as VII/145 ====Sorry, no entry could be found====