Nambu-Goto Like Action for the AdS_5 x S^5 Superstrings in the   Generalized Light-Cone Gauge
  We reinvestigate the kappa-symmetry-fixed Green-Schwarz action in the AdS_5 x S^5 background in a version of the light-cone gauge. In the generalized light-cone gauge, the action has been written in the phase space variables. We convert it into the standard action written in terms of the fields and their derivatives. We obtain a Nambu-Goto type action which has the correct flat-space limit. 
Hiroshi Itoyama, Takeshi Oota and Reiji Yoshioka