Cnoidal wave solutions for a class of fifth-order KdV equations

A suitable ansatz and Jacobi elliptic function expansion method are used to construct new exact cnoidal wave solutions of the modified fifth-order Korteweg-de Varies (KdV) equation and the generalized fifth-order KdV equation which includes, as special cases, some well-known equations. When the modulus of the Jacobi elliptic function m→1, the corresponding solitary wave solutions are also obtained.