Space Symmetries and Quantum Behavior of Finite Energy Configurations in   SU(2)-Gauge Theory
  The quantum properties of localized finite energy solutions to classical Euler-Lagrange equations are investigated using the method of collective coordinates. The perturbation theory in terms of inverse powers of the coupling constant $g$ is constructed, taking into account the conservation laws of momentum and angular momentum (invariance of the action with respect to the group of motion M(3) of 3-dimensional Euclidean space) rigorously in every order of perturbation theory. 
A. V. Shurgaia, H. J. W. Mueller-Kirsten