1. N. N. Moiseev, Yu. P. Ivanilov, and E. M. Stolyarova, Optimization Methods (Nauka, Moscow, 1978) [in Russian].
2. L. S. Pontryagin, V. G. Boltyanskii, R. V. Gamkrelidze, and E. F. Mishchenko, Mathematical Theory of Optimal Processes (Nauka, Moscow, 1961; Gordon and Breach, New York, 1986).
3. F. L. Chernous’ko and N. V. Banichuk, Variational Problems in Mechanics and Control (Numerical Methods) (Nauka, Moscow, 1973) [in Russian].
4. R. Bellman, Dynamic Programming (Princeton Univ. Press, Princeton, 1957; Inostrannaya Literatura, Moscow, 1960).
5. F. L. Chernous’ko, L. D. Akulenko, and B. N. Sokolov, Control of Oscillations (Nauka, Moscow, 1980) [in Russian].