Asmaâ Moujib

We Construct the generalized Monodromy Matrix M(?) of Two-dimensional string effective action by introducing the T-duality group properties. The integrability conditions with general solutions depending on spectral parameter are given following the currents which correspond to the zero curvature condition. This construction is investigated for the exactly solvable Wess, Zumino, Nappi and Witten model when B=0. This cosmological model describes an expanding universe.