1. Clusters of Atoms and Molecules, Vol. I, edited by H. Haberland (Springer, Heidelberg, 1991)
2. Large Clusters of Atoms and Molecules, edited by T.P. Martin (Kluwer, Dordrecht, 1996)
3. Atomic Clusters and Nanoparticles, edited by C. Guet, P. Hobza, F. Spiegelman, F. David (Nato Advanced Study Institute Les Houches LXXIII, EDP Sciences, Paris, and Springer, Berlin, 2000)
4. R.L. Johnston, Atomic and Molecular clusters (Taylor and Francis, London, 2002)
5. O. Echt, K. Sattler, E. Recknagel, Phys. Rev. Lett. 47, 16 (1981)