1. P. G. De Gennes, P. A. Pincus, F. Hartmann-Bourton, and J. M. Winter, Phys. Rev. 129, 105 (1963).
2. A. V. Andrienko, V. I. Ozhogin, V. L. Safonov, and A. Yu. Yakubovskii, Usp. Fiz. Nauk 161(10), 1 (1991) [Sov. Phys. Usp. 34, 843 (1991)].
3. V. S. L’vov, Nonlinear Spin Waves (Nauka, Moscow, 1987) [in Russian].
4. A. V. Andrienko, V. L. Safonov, and A. Yu. Yakubovskii, Zh. Éksp. Teor. Fiz. 93, 907 (1987) [Sov. Phys. JETP 66, 511 (1987)].
5. A. S. Mikhailov and I. B. Uporov, Zh. Éksp. Teor. Fiz. 77, 2383 (1979) [Sov. Phys. JETP 50, 1149 (1979)].