1. Backlund Transformations;Miura,1987
2. Symmetries and Differential Equations;Bluman,1989
3. Solitons, Nonlinear Evolution Equations and Inverse Scattering;Ablowitz,1991
4. Darboux Transformations and Solitons;Matveev,1991
5. Applications of Lie Groups to Differential Equations;Olver,1993