1. A. Pikovskii, M. Rozenblyum, and J. Kurths, Synchronization. A Fundamental Nonlinear Phenomenon (Tekhnosfera, Moscow, 2003) [in Russian].
2. P. Hanggi and P. Jung, Adv. Chem. Phys. 89, 239 (1995).
3. S. M. Rytov, Introduction to Statistical Radiophysics, Part 1: Random Processes (Nauka, Moscow, 1976) [in Russian].
4. W. Horsthemke and R. Lefever, Noise Induced Transitions: Theory and Applications in Physics, Chemistry, and Biology (Springer, Heidelberg, 1984; Mir, Moscow, 1987).
5. S. A. Guz and M. V. Sviridov, Phys. Lett. A 240(1–2), 43 (1998).