Radiative corrections to muon decay in leading and next to leading   approximation for electron spectrum
  We have noted that the electron spectrum of muon decay in the leading logarithmic approximation calculated in two lowest orders of the perturbation theory in the paper of Berman (1958), can be reproduced by the parton language. This fact permits one to generalize the result to all orders of the perturbation theory using the structure function method. 
E. Bartos, E. A. Kuraev, M. Secansky