1. V. I. Arnold: Mathematical Methods of Classical Mechanics. Springer-Verlag, GTM 60, Berlin, Second edition, (1989).
2. G. Dahlquist: Error analysis for a class of methods for stiff nonlinear initial value problems. In G.A. Watson, editor, Lecture Notes in Mathematics, Vol. 506, Numerical Analysis, Dundee, pages 60–74. Springer, Berlin, (1975).
3. A. J. Dragt and J. M. Finn: Lie series and invariant functions for analytic symplectic maps. J. of Math. Phys., 17:2215–2227, (1976).
4. A.J. Dragt and E. Forest: Computation of nonlinear behavior of Hamiltonian systems using Lie algebraic methods. J. of Math. Phys., 24(12):2734–2744, (1983).
5. K. Feng: On difference schemes and symplectic geometry. In K. Feng, editor, Proceedings of the 1984 Beijing Symposium on Differential Geometry and Differential Equations, pages 42–58. Science Press, Beijing, (1985).