1. Kulebakin, V., To the Theory of Automatic Vibrational Regulators for Electric Motors, Teor. Eksp. Elektron., 1932, no. 4, pp. 3–21.
2. Flugge-Lotz, I., Discontinuous Automatic Control, New Jersey: Princeton Univ. Press, 1953.
3. Tsypkin, Ya., Teoriya releinykh sistem avtomaticheskogo regulirovaniya (Theory of Relay Control Systems), Moscow: Gostekhizdat, 1955.
4. Nikolskii, G.N., On Automatic Stability of a Ship on the Given Course, Tr. Tsentr. Lab. Provodnoi Svyazi, 1934, no. 1, pp. 34–75.
5. Proc. 2nd All Union Control Conf., Discussion, 1955, vol. v, pp. 460–462.