Three-loop renormalization of the N=1, N=2, N=4 supersymmetric   Yang-Mills theories
  We calculate the renormalization constants of the N=1, N=2, N=4 supersymmetric Yang-Mills theories in an arbitrary covariant gauge in the dimensional reduction scheme up to three loops. We have found, that the beta-functions for N=1 and N=4 SYM theories are the same from the different triple vertices. This means that the dimensional reduction scheme works correctly in these models up to third order of perturbative theory. 
V.N. Velizhanin (St. Petersburg, INP)