Renormalization and asymptotic states in Lorentz-violating QFT
  Radiative corrections in quantum field theories with small departures from Lorentz symmetry alter structural aspects of the theory, in particular the definition of asymptotic single-particle states. Specifically, the mass-shell condition, the standard renormalization procedure as well as the Lehmann-Symanzik-Zimmermann reduction formalism are affected. 
Mauro Cambiaso, Ralf Lehnert and Robertus Potting
hep-ph