1. Exact results on potential models for quarkonium systems;Grosse;Phys. Rep.,1980
2. Two theorems on the level order in potential models;Grosse;Phys. Lett. B,1984
3. Energy levels and level ordering in the WKB approximation;Feldman;Nucl. Phys. B,1979
4. Applications à la physique des particles et à la physique atomique d'un “theorème” sur l'ordre des niveaux d'énergie;Grosse;C.R. Acad. Sci. Paris Ser. II, Méc. Phys. Chim. Sci.,1984
5. H. Grosse and A. Pflug, On the structure of the periodic system, Amer. J. Phys., in press.