1. F. L. Chernous’ko, L. D. Akulenko, and B. N. Sokolov, Control of Oscillations (Nauka, Moscow, 1980) [in Russian].
2. V. M. Mamalyga, “Optimal control of one oscillatory system,” Izv. Akad. Nauk SSSR, Mekh. Tverd. Tela, No. 3, 8–17 (1978).
3. L. S. Pontryagin, V. G. Boltyanskii, R. V. Gamkrelidze, and E. F. Mishchenko, Mathematical Theory of Optimal Processes (Nauka, Moscow, 1969; Wiley, New York, London, 1962).
4. O. R. Kayumov, “Optimal control of an elliptical pendulum,” Izv. Akad. Nauk SSSR, Mekh. Tverd. Tela, No. 4, 38–44 (1985).
5. O. R. Kayumov, “On the global controllability of some lagrangian systems,” Izv. Akad. Nauk SSSR, Mekh. Tverd. Tela, No. 6, 16–23 (1986).