Bar Galaxies and their Environments
  The prints of the Palomar Sky Survey, luminosity classificaiton and radial velocities were used to assign all northern Shapley-Ames galaxies to either (1) field, (2) group, or (3) cluster environments. This information for 930 galaxies shows no evidence for a dependence of bar frequency on galaxy environment. This suggests that the formation of a bar in a dish galaxy is mainly determined by the properties of the parent galaxy, rather than by the characteristics of its environment. 
Sidney van den Bergh (DAO, HIA, NRCC)