SpaceTime Duality And $SU(n,1)\over SU(n)\otimes U(1)$ Cosets Of   Orbifold Compactification
  The duality symmetry group of the cosets ${\textstyle SU(n,1)\over \textstyle SU(n)\otimes U(1)}$, which describe the moduli space of a two-dimensional subspace of an orbifold model with $(n-1)$ complex Wilson lines moduli, is discussed. The full duality group and its explicit action on the moduli fields are derived. 
W. A. Sabra