1. K. Rademann, B. Kaiser, U. Even, and F. Hensel, Phys. Rev. Lett. 59, 2319 (1997); C. Brechignac, M. Broyer, P. Cahuzac, G. Delacretaz, P. Labastie, J. P. Wolf, and L. Wöste, ibid. 60, 275 (1988); M.E. Garcia, G. M. Pastor, and K. Bennemann, ibid. 67, 1142 (1991); K. Rademann, O. Dimopoulou-Rademann, M. Schiauf, U. Even, and F. Hensel, ibid. 69, 3208 (1992); H. Haberland, B. von Issendorf, Y. Yufeng, and T. Kolar, ibid. 69, 3212 (1992); G. M. Pastor and K. Bennemann, in Clusters of Atoms and Molecules, Vol. 1, H. Haberland (Ed.), Springer-Verlag, Heidelberg, 1994; R. Busani, M. Folkers, and O. Cheshnovsky, Phys. Rev. Lett. 81, 3836(1998)
2. D. A. McQuarrie,Statistical Mechanics, Harper & Row, New York, 1976
3. Physics and Chemistry of Small Clusters, P. Jena, B. K. Rao, and S. N. Khanna (Eds.), Plenum Press, New York, 1987
4. Elemental and Molecular Clusters, G. Benedek, T. P. Martin, and G. Pacchioni (Eds.), Springer-Verlag, Berlin, 1988
5. Physics and Chemistry of Finite Systems: From Clusters to Crystals, Vols. 1 and 2, P. Jena, S. N. Khanna, and B.K. Rao (Eds.), Kluwer Academic Publishers, Dordrecht, 1992