Exact Scale Invariance of the BF-Yang-Mills Theory in Three Dimensions
  The ``extended'' BF-Yang-Mills theory in 3 dimensions, which contains a minimally coupled scalar field, is shown to be ultraviolet finite. It obeys a trivial Callan-Symanzik equation, with all beta-functions and anomalous dimensions vanishing. The proof is based on an anomaly-free trace identity valid to all orders of perturbation theory. 
Oswaldo M. Del Cima, Daniel H. T. Franco, Jose A. Helayel-Neto and   Olivier Piguet