1. See, for example, J.G. Dash:Films on Solid Surfaces (Academic Press, New York 1975)
2. J.P. McTague, M. Nielsen, L. Passell: InPhase Transitions in Surface Films ed. by J.G. Dash, J. Ruvaldo (Plenum Press, New York 1980)
3. See, for example, G.A. Somorjai:Chemistry in Two Dimensional Surfaces (Cornell Press, Ithaca, NY 1982)
4. See examples, P. Hautojärvi (ed.):Positrons in Solids, Topics Current Phys.12 (Springer, Berlin, Heidelberg, New York 1979)
5. W. Brandt, A. Dupasquier:Positron Solid-State Physics (North-Holland, Amsterdam 1983)