Scattering States and Symmetries in the Matrix Model and Two Dimensional   String Theory
  We study the correspondence between the linear matrix model and the interacting nonlinear string theory. Starting from the simple matrix harmonic oscillator states, we derive in a direct way scattering amplitudes of 2-dimensional strings, exhibiting the nonlinear equation generating arbitrary N-point tree amplitudes. An even closer connection between the matrix model and the conformal string theory is seen in studies of the symmetry algebra of the system. 
A. Jevicki, J. P. Rodrigues, A. J. van Tonder (Brown)