1. Mathematical Methods of Classical Mechanics, 2nd edition, Graduate Texts in Mathematics 60 (Springer-Verlag, New York etc., 1989), Chap. 10, Appendices 7 and 8.
2. , and , Mathematical Aspects of Classical and Celestial Mechanics, 3rd edition, Encyclopaedia of Mathematical Sciences 3, Dynamical Systems III (Springer-Verlag, Berlin etc., 2006), Chaps. 5 and 6.
3. Classical Mathematical Physics, Dynamical Systems and Field Theories, 3rd edition (Springer, New York etc., 1997), Chaps. 2 and 3.
4. Vorlesungen über Atommechanik, herausg. unter Mitwirkung von F. Hund, Bd. 1 (Struktur der Materie in Einzeldarstellungen II; Verlag Julius Springer, Berlin, 1925); English translation: The Mechanics of the Atom (G. Bell and Sons, Ltd., London, 1927), reprinted (Frederick Ungar Publ. Co., New York, 1960).
5. �ber quantentheoretische Umdeutung kinematischer und mechanischer Beziehungen.