The hierarchy of the sine-Gordon equation with self-consistent sources is derived by using the eigenfunctions of recursion operator. The bilinear form of the sine-Gordon equation with self-consistent sources is given and the N-soliton solutions are obtained through Hirota method and Wronskian...

The bilinear form of the non-isospectral mKdV equation is given and the exact N-soliton solutions are obtained through Hirota method and Wronskian technique, respectively.