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2. Frenkel, Y.I., Kontorova, T.: Zh. Eksp. Teor. Fiz.8, 1340 (1938)
3. Frank, F.C., van der Merve: Proc. R. Soc. LondonA198, 205, 216 (1949)
4. Luther, A., Timmonen, J., Pokrovsky, V.: Phase transitions in surface films. New York: Plenium Press 1980.
5. Currat, R., Janssen, T.: Solid state physics, vol. 41. New York: Academic Press 1988