1. S. D. Glyzin, A. Yu. Kolesov, and N. Kh. Rozov, Differ. Equations 41, 41–49 (2005) [Differ. Uravn. 41, 41–49 (2005)].
2. A. Yu. Kolesov and N. Kh. Rozov, Invariant Tori of Nonlinear Wave Equations (Fizmatlit, Moscow, 2004) [in Russian].
3. E. F. Mishchenko, V. A. Sadovnichii, A. Yu. Kolesov, and N. Kh. Rozov, Autowave Processes in Nonlinear Diffusive Media (Fizmatlit, Moscow, 2005) [in Russian].
4. Yu. L. Daletskii and M. G. Krein, Stability of Solutions to Differential Equations in Banach Spaces (Nauka, Moscow, 1970) [in Russian].
5. Software Package TRASER 3.51 for Numerical Integration of Systems of Differential Equations, http://traser3.narod.ru .