Symmetries of Toda Equations
  We find a sequence consisting of time dependent evolution vector fields whose time independent part corresponds to the master symmetries for the Toda equations. Each master symmetry decomposes as a sum consisting of a group symmetry and a Hamiltonian vector field. Taking Lie derivatives in the direction of these vector fields produces an infinite sequence of recursion operators. 
Pantelis A. Damianou
math-ph math.MP