1. B. E. Zakharov and E. A. Kuznetsov, Phys. Usp. 55, 535 (2012).
2. N. Akhmediev and A. Ankiewicz, Solitons. Non-Linear Pulses and Beams (Fizmatlit, Moscow, 2003; Springer, US, 1997).
3. G. I. Stegeman and M. Segev, Science (Washington, DC, U. S.) 286, 1518 (1999).
4. S. A. Akhmanov, B. A. Vysloukh, and A. C. Chirkin, Optics of Femtosecond Laser Pulses (Nauka, Moscow, 1988
5. Am. Inst. Phys., College Park, 1992).