Optical and HI properties of isolated galaxies in the 2MIG catalog. I.   General relationships
  We analyze empirical relationships between the optical, near infrared, and HI characteristics of isolated galaxies from the 2MIG Catalog covering the entire sky. Data on morphological types, K_S-, and B-magnitudes, linear diameters, HI masses, and rotational velocities are examined. The regression parameters, dispersions, and correlation coefficients are calculated for pairs of these characteristics. The resulting relationships can be used to test the hierarchical theory of galaxy formation through numerous mergers of cold dark matter. 
Yu. N. Kudrya, V. E. Karachentseva, and I. D. Karachentsev
astro-ph.CO