Minimizing gauge-functional for 2-d gravity and string theory
  We show the existence of a minimizing procedure for selecting a unique representative on the orbit of any given Riemann surface that contributes to the string partition function. As it must, the procedure reduces the string path integral to a final integration over a particular fundamental domain, selected by the choice of the minimizing functional. This construction somehow demystifies the Gribov question. 
Laurent Baulieu and Daniel Zwanziger
hep-th