Applications of sine-Gordon expansion method for a reliable treatment of some nonlinear wave equations.

This aim of this paper is threefold. A survey of trigonometric-hyperbolic function methods for constructing solitary wave solutions of nonlinear equations. Further analysis of the sine-Gordon expansion method. Studying the solution ol the generalized PHI-four equation and the generalized regularized long wave equation by using a special transformation derived from the Sine-Gordon equation. [ABSTRACT FROM AUTHOR]