1. Arnold, V.I., Avez, A.: Ergodic problems of classical mechanics. Benjamin, NY (1968)
2. Arnold, V.I.: Proof of a theorem of A.N. Kolmogorov on the preservation of conditionally periodic motions under a small perturbation of the Hamiltonian. Uspekhi Mat. Nauk, 18, 13-40 (1963)
3. Arnold, V.I.: Mathematical methods of classical mechanics. Springer Verlag (1985)
4. Benettin, G., Galgani, L., Giorgilli, A., Strelcyn, J.-M.: A proof of Kolmogorov’s theorem on invariant tori using canonical transformations defined by the Lie method. Il Nuovo Cimento, 79B (1984)
5. Fathi, A., Herman, M.: Sur les courbes invariantes par les difféomorphismes de l’anneau. Astérisque, 103-104 (1983)