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2. A. Braison and Kho Yu-shi, Applied Theory of Optimal Control [Russian translation], Mir, Moscow (1972).
3. E. A. Koddington and N. Levinson, Theory of Ordinary Differential Equations [Russian translation], Izd. Inostr. Lit., Moscow (1958).
4. J. Riordan, Combinatorial Identities, John Wiley & Sons, Inc., New York-London-Sydney (1968).
5. E. Ya. Smirnov, Some Problems of Mathematical Control Theory [in Russian], Izd. Leningr. Univ., Leningrad (1981).