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2. B. L. Van der Waerden, Modern Algebra [Russian translation], Gostekhizdat, Moscow–Leningrad (1934).
3. I. V. Gaishun, Introduction to the Theory of Linear Nonstationary Systems [in Russian], Inst. Mat. NAN Belarusi, Minsk (1999).
4. V. I. Zubov, Lectures on Control Theory [in Russian], Lan’, St.-Petersburg (2009).
5. G. Leitmann, An Introduction to Optimal Control, McGraw-Hill, New York (1966).