Comments on: "Optical solitons in a parabolic law media with fourth order dispersion"[Appl. Math. Comput. 208(2009)209-302]

Abstract

Recently, Biswas and Milovic [Appl. Math. Comput. 208 (2009) 209-302] have found optical one-soliton solutions of a fourth order dispersive cubic-quintic nonlinear Schr\"odinger equation. In this comment, we first show there are mistakes in the paper and demonstrate that the obtained solutions do not satisfy the considered equation. And then we reconstruct a series of analytical exact solutions by means of a direct ansatz method and F-expansion method. These solutions include solitary wave solutions of the bell shape, solitary wave solutions of the kink shape, and periodic wave solutions of Jacobian elliptic function.