1. M. I. Rabinovich and D. I. Trubetskov, Introduction to Theory of Oscillations and Waves (Nauka, Moscow, 1984)
2. A. S. Pikovsky and M. I. Rabinovich, Physica 2D, 8 (1981).
3. M. I. Rabinovich, Sov. Phys. Usp. 21, 443 (1978).
4. A. S. Pikovskii, Izv. Vyssh. Uchebn. Zaved., Radiofiz. 23, 883 (1980).
5. A. V. Skripal’, D. A. Usanov, and A. V. Abramov, Izv. Vyssh. Uchebn. Zaved., Prikl. Nelin. Din. 8 (4), 66 (2000).