Radio map of MESSIER 033 region; Reference is 1974A&A....32..363I

   Fig. 1. Radio map of M 33. The dashed contour level is at 1.2, the others
 are from 1.8-6.0 mfu per beam in steps of 0.6 mfu per beam. The field center
 of the map is indicated by a cross. The numbers refer to sources identified
 with H II regions and summarized in Table 2a, the letters refer to the
 unidentified sources in Table 2b.