Is the Hubble type of a disk system essentially determined by one parameter: total mass

In this paper the claim is made that, for gas-rich disk galaxies, there are good correlations between each pair of the triad: mass, luminosity, and color. It is asked if there is any additional information in the morphological classification of individual galaxies, in the sense that part of the scatter in these relations might be due to systematic variations with type. (Auth.)