1. Moriwaki, T., Shiromaru, H., Achiba, Y.: In: Physics and Chemistry of Finite Systems. p. 447 Jena, P., Khanna, S.N., Rao, B.K. (eds.). Dordrecht, Boston, London: Kluwer 1992
2. Moriwaki, T., Matsuura, H., Aihara, K., Shiromaru, H., Achiba, Y.: J. Phys. Chem., submitted
3. Beck, R.D., St.John, P., Alvarez, M.M., Diederich, F., Whetten, R.L.: J. Phys. Chem.,95 8402 (1991)
4. Yeretzian, C., Whetten, R. L.: Z. Phys. D.,24 199 (1992)
5. Kr�tschmer, W., Lamb, L. D., Fostiropoulos, K., Huffman, D. R.: Nature,347 354 (1990)