1. Abraham, R., Marsden, J.E.: Foundations of Mechanics. London: The Benjamin/Cummings Publishing, 1978
2. Arnold, V.I.: Proof of A.N. Kolmogorov's theorem on the preservation of quasi-periodic motions under small perturbation of the Hamiltonian. Uspekhi Mat. Nauk. U.S.S.R.18, Ser.5, 13–40 (1963)
3. Arnold, V.I.: Mathematical methods of classical mechanics. Berlin, Heidelberg, New York: Springer, 1978
4. Birkhoff, G.D.: Dynamical systems. Providence, Rhode Island: American Mathematical Society, 1966
5. Bogoyavlenskij, O.J.: Invariant incompatible Poisson structures. Proc. R. Soc. Lond. A450, 723–730 (1995)