1. L. V. Ovsyannikov, in Dynamics of Continuous Media (Nauka Novosibirsk, 1973), No. 15, p. 104 [in Russian].
2. L. V. Ovsjannikov, Arch. Mech. 26, 407 (1974).
3. A. I. Dyachenko, E. A. Kuznetsov, M. D. Spector, and V. E. Zakharov, Phys. Lett. A 221, 73 (1996).
4. A. I. Dyachenko, Y. V. Lvov, and V. E. Zakharov, Phys. D (Amsterdam, Neth.) 87, 233 (1995).
5. A. I. D’yachenko, V. E. Zakharov, and E. A. Kuznetsov, Plasma Phys. Rep. 22, 829 (1996).