1. Lie-Bäcklund Transformations in Applications;Anderson,1979
2. On a new hierarchy of symmetries for the integrable nonlinear evolution equations;Chen,1982
3. Symmetries for dynamical and Hamiltonian Systems;ten Eikelder,1985
4. Bäcklund Transformations for Hereditary Symmetries;Fokas;Nonlinear Analysis TMA,1981
5. The hierarchy of the Benjamin-Ono Equation;Fokas;Phys. Lett. A,1981