1. Wohlleben, D.K.: In: Valence Fluctuations in Solids. Falicov, L.M., Hanke, W., Maple, M.B. (eds.) p. 1. Amsterdam, Oxford, New York: North Holland (1981)
2. Neumann, G., Pott, R., Röhler, J., Schlabitz, W., Wohlleben, D., Zahel, H.: In: Valence Instabilities. Wachter, P., Boppart, H. (eds.), p. 87. Amsterdam, Oxford, New York: North Holland 1982
3. Wohlleben, D.K.: In: Proc. of ASI on “Moment Formation in Solids”. Pearson College, Vancouver Island (Aug. 1983). Buyers, W. (ed.) New York, London: Plenum Press 1984
4. Allen, J.W., Martin, R.M.: Phys. Rev. Lett.49, 1106 (1982)
5. Lavagna, M., Lacroix, C., Cyrot, M.: Phys. Lett.90 A, 210 (1982)