1. See, e.g., Jackson, K.A.: In: Crystal growth and characterisation. Uedo, R., Mullin, J.B. (eds.), pp. 21?32. Amsterdam: North Holland 1975
2. Müller-Krumbhaar, H.: In: Festkörperprobleme XIX. pp. 1?20. Braunschweig: Vieweg 1979; In: Lectures at the Nato Summer School, Cargese, 1982
3. Balibar, S., Castaing, B.: J. Phys. (Paris) Lett.41, 329 (1980);
4. Wolf, P.E., Gallet, F., Balibar, S., Rolley, E., Nozieres, P.: J. Phys. (Paris)46, 1987 (1985)
5. Avron, J.E., Balfour, L.S., Kuper, C.G., Landau, J., Lipson, S.G., Schulman, L.S.: Phys. Rev. Lett.45, 814 (1980)