1. Bogoliubov, N.N. and Mitropolsky, Yu.A., Asymptotic Methods in the Theory of Non-Linear Oscillations,
Dehli: Hindustan Publ. Corp., 1961.
2. Malkin, I.G., Nekotorye zadachi teorii nelineinykh
kolebanii (Some Problems in the Theory of Nonlinear Oscillations), Moscow:
Gostekhizdat, 1956.
3. Zhuravlev, V.F. and Klimov, D.M., Prikladnye metody v teorii
kolebanii (Applied Methods in the Theory of Oscillations), Moscow:
Nauka, 1988.
4. Grebenikov, E.A., and Ryabov, Yu.A.,
Konstruktivnye metody analiza nelineinykh sistem, Moscow: Nauka, 1979. Translated
under the title: Constructive Methods in the Analysis of Nonlinear
Systems, Moscow: Mir, 1983.
5. Guckenheimer, J. and Holmes, P., Nonlinear
Oscillations, Dynamical Systems and Bifurcations of Vector Fields, New York:
Springer, 1983. Translated under the title: Nelineinye kolebaniya,
dinamicheskie sistemy i bifurkatsii vektornykh polei, Moscow–Izhevsk: Inst.
Komp’yut. Issled., 2002.