References
- Benjamin , T.B. , Bona , I.L. and Mahony , J.J. 1972 . Model equations for long v/aves in nonlinear dispersive systems . Philos. Trans. Roy. Soc. Lond , 272A : 47 – 78 .
- Jeffrey , A. 1972 . Nonlinear wave propagation . Zeit. Ange. Math. Meek (ZAMM) , 272A