1. A. Hasegawa, Y. Kodama, Solitons in Optical Communications, Clarendon Press, Oxford, 1995.
2. G.P. Agrawal, Nonlinear Fiber Optics, 2nd ed., Academic Press, San Diego, 1995.
3. N.N. Akhmediev, A. Ankiewicz, Solitons: Nonlinear Pulses and Beams, Chapman and Hall, New York, 1997.
4. Collapse of optical pulses
5. Variational approach to collapse of optical pulses