1. Long, R. R. 1946 Solitary waves in one and two-fluid systems.Tellus,8,460.
2. Benjamin, T. B. & Lighthill, M. J. 1954 On cnoidal waves and bores.Proc. Roy. Soc. A 224,448.
3. Serrin, J. B. 1952b Two hydrodynamic comparison theorems.J. Rat. Mech. Anal. 1,563.
4. Lavrentiev, M. A. 1964 Variational Methods. Noordhoff.
5. Starr, V. P. 1947 Momentum and energy integrals for gravity waves of finite height.J. Mar. Res. 6,176.