1. S. V. Manakov, Funktsion. Analiz Prilozh. 10 (4), 93 (1976).
2. A. P. Veselov, Dokl. Akad. Nauk 270 (6), 1298 (1983).
3. O. I. Bogoyavlenskii, Dokl. Akad. Nauk 287 (5), 1105 (1986).
4. V. A. Samsonov and M. V. Shamolin, Vestn. Mosk. Univ. Ser. Mat. Mekh., No. 3, 51 (1989).
5. M. V. Shamolin, Method of Analysis of Dynamic Sets with Variable Dissipation in Dynamics of Solid (Ekzamen, Moscow, 2007) [in Russian].