G.P. Agrawal. Nonlinear Fiber Optics, Academic, San Diego,
 P.N. Butcher and D. Cotter, The Elements of Nonlinear Op-
tics, Cambridge University Press, 1991.
 Y.S. Kivshar, G. P. Agrawal, Optical Solitons, 2003.
 J.H.B. Nijhof, H.A. Ferwerda, and B.J. Hoenders, Derivation
of the equation for an ultrashort pulse in a fibre, Pure Appl.
Opt. 4, 199-218 (1994).
 A. Hasegawa and Y. Kodama, Solitons in optical communi-
cation, Oxford University Press, New York, 1995.
 G.P. Agrawal and M.J. Potasek, Nonlinear pulse distortion in
single mode optical fibers at the zero-dispersion wavelength,
Phys Rev 33(3), 1765-1776 (1986).
 M. Facăo, M. I. Carvalho, Soliton self-frequency shift: Self-
similar solutions and their stability, Physical Review E 81,
 H. P. Tian, Z. H. Li, Z. Y. Xu, J. P. Tian, and G. S. Zhou,
Stablesoliton in the fiber-optic system with self-frequency
shift, J. Opt.Soc. Am. B 20, 59-64 (2003).
 Zhongxi Zhang, Liang Chen, and Xiaoyi Bao, A fourth-order
Runge-Kutta in the interaction picture method for numeri-
cally solving the coupled nonlinear Schrödinger equation,
Optics Express 8, 8261-8276 (2010).
 J.M. Dudley, J.R.Taylor, Supercontinuum Generation in opti-
cal fibers, Cambridge, 2010.
 Van Cao Long, Rev. Adv. Mater. Sci. 23 8-24 (2010).
Do Thanh Thuy, Bui Dinh Thuan, Dinh Xuan Khoa, Nguyen
Thanh Vinh, Cao Long Van, to be published.