1. A. A. Andronov, A. A. Vitt, and S. E. Khaikin, Theory of Oscillations (Fizmatgiz, Moscow, 1959) [in Russian].
2. V. N. Rubanovskii and V. A. Samsonov, Stability of Stationary Motions in Examples and Problems (Nauka, Moscow, 1988) [in Russian].
3. T. G. Strizhak, Methods of Studying Dynamic Pendulum Systems (Nauka, Alma-Ata, 1981) [in Russian].
4. I. I. Blekhman, Vibrational Mechanics (Nauka, Moscow, 1994) [in Russian].
5. O. V. Kholostova, Problems of the Dynamics of Solids with an Oscillating Suspension (Inst. Comput. Invest., Izhevsk, 2016) [in Russian].