1. Parametrical (soliton like) solutions of integrable systems as subclass of solutions depending on a set of arbitrary functions;Leznov,1991
2. Proceedings of Conference;Leznov,1992
3. Nonlinear symmetries of integrable systems;Leznov;J. of Sov. Lazer. Research,1992
4. Backlund transformation for integrable systems;Leznov;preprint IHEP-92-112 DTP,1992
5. The canonical symmetry for integrable systems;Leznov;J. Math. Phys.,1994