1. (Ed.), Valence Instabilities and Related Narrow Band Phenomena, Plenum Press, New York 1977).
2. in: Handbook on the Physics and Chemistry of Rare Earths, Ed. and , North-Holland Publ. Co., Amsterdam 1979 (p. 575).
3. Intermediate valency
4. , and (Ed.), Valence Fluctuations in Solids, North-Holland Publ. Co., Amsterdam 1981.
5. and (Ed.), Valence Instabilities, North-Holland Publ. Co., Amsterdam 1982.