1. Pontryagin, L.S., Obyknovennye differentsial’nye uravneniya (Ordinary Differential Equations), Moscow: Nauka, 1974.
2. Cesari, L., Asymptotic Behavior and Stability Problems in Ordinary Differential Equations, Berlin, 1959. Translated under the title Asimptoticheskoe povedenie i ustoichivost’ reshenii obyknovennykh differentsial’nykh uravnenii, Moscow, 1964.
3. MacLachlan, N.W., Theory and Application of Mathieu Functions, Oxford: Clarenden Press, 1947. Translated under the title Teoriya i prilozhenie funktsii Mat’e, Moscow, 1953.
4. Adrianova, L.Ya., Vvedenie v teoriyu lineinykh sistem differentsial’nykh uravnenii (Introduction to the Theory of Linear Systems of Differential Equations), St.-Petersburg: Izd. St.-Peterb. Univ., 1992.
5. Yakubovich, V.A. and Starzhinskii, V.M., Lineinye differentsial’nye uravneniya s periodicheskimi koeffitsientami i ikh prilozheniya (Linear Differential Equations with Periodic Coefficients and Their Applications), Moscow: Nauka, 1972.