1. Arnold, V. I.: 1974,Mathematical Foundations of Classical Mechanics, translated from Russian by A. Weinstein, Springer-Verlag, New York, Heidelberg, Berlin.
2. Bargmann, V.: 1936,Z. Phys. 99, 576.
3. Boigey, F.: 1977,Compt Roy Acad. Sci. Paris284, 911.
4. Boigey, F.: 1981, These de doctorat d'�tat, Universit� Pierre et Marie Curie, Paris.
5. Born, M.: 1925,Vorlesungen �ber Atommechanik, Verlag von Julius Springer, Berlin; translated into English under the titleThe Mechanics of the Atom, Bell London, 1927.