1. Abraham, R., Marsden, J.: Foundations of Mechanics, 2nd ed. Reading, Mass.: Benjamin-Cummings. 1978.
2. Arnold, V.: Mathematical Methods of Classical Mechanics. New York-Heidelberg-Berlin: Springer. 1978.
3. Burgoyne, N., Cushman, R.: Normal forms for real linear Hamiltonian systems. In: The 1976 NASA Conference on Geometric Control Theory, pp. 483?529. Ed. C. Martin and R. Hermann. 1977. Math. Sci. Press.
4. Burgoyne, N., Cushman, R.: Conjugacy classes in linear groups. J. Algebra44, 339?362 (1977).
5. Cushman, R.: The momentum mapping of the harmonic oscillator. Symposia Mathematica XIV, 323?342 (1974).