The Frequency of Active and Quiescent Galaxies with Companions
  We study the percentage of active, HII and quiescent galaxies with companions in the Palomar survey. We find that when we separate the galaxies by their morphological types (ellipticals or spirals), to avoid morphology-density effects, there is no difference in the percentage of galaxies with companions among the different activity types. 
Henrique R. Schmitt (NRAO)