1. M. Guzman, M. Romagnoli, and S. Wabnitz, Appl. Phys. Lett. 56, 614 (1990).
2. F. Kh. Abdullaev, S. A. Darmanyan, and V. I. Goncharov, Pis’ma Zh. Tekh. Fiz. 18(14), 29 (1992) [Sov. Tech. Phys. Lett. 18, 448 (1992)].
3. F. Kh. Abdullaev and R. Gulyamov, Pis’ma Zh. Tekh. Fiz. 18(20), 10 (1992) [Sov. Tech. Phys. Lett. 18, 653 (1992)].
4. F. Kh. Abdullaev, S. A. Darmanyan, and P. K. Khabibulaev, Optical Solitons (Fan, Tashkent, 1987), p. 200.
5. A. A. Maier, Usp. Fiz. Nauk 166, 1171 (1996) [Phys. Usp. 39, 1109 (1996)].