1. Beeby, J.L., 1973, J. Phys. C. 6, 2262
2. Bernal, J.D. and Fowler,R.H., 1933, J. Chem. Phys. 1, 55
3. Brady, G.W., 1958, J. Chem. Phys. 28, 464, Proc. Roy. Soc. A, 255, 558
4. Bockris, J.O.M., Crook, E.H., Bloom, H. and Richards, N.E., 1960 Proc. Roy. Soc. A 255, 558
5. Boyce, J.B. and Mikkelson, J.C., 1977, J. Phys. C. 10, L41