1. Åströom, K. J. and K. Furuta [1996], Swinging up a pendulum by energy control, IFAC World Congress, San Francisco 13.
2. Abraham, R. and J. E. Marsden [1978], Foundations of Mechanics, Second Edition, Addison-Wesley.
3. Auckly, D., L. Kapitanski, and W. White [2000], Control of nonlinear underactuated systems, Comm. Pure Appl. Math., 53, 354–369.
4. Baillieul, J. [1999], Matching conditions and geometric invariants for second-order control systems, in Proc. IEEE Conf. Decision and Control 38, 1664–1670.
5. Bloch, A. M., D. E. Chang, N. E. Leonard, and J. E. Marsden [2001], Controlled Lagrangians and the stabilization of mechanical systems II: Potential shaping, IEEE Trans. Automatic Control 46, 1556–1571.