1. Acosta, J.A., Ortega, R., Astolfi, A., and Mahindrakar, A.D. (2005). Interconnection and damping assignment passivity-based control of mechanical systems with un-deractuation degree one. IEEE Trans. Autom. Control, 50, 1936–1955.
2. Arnold, V.I., Kozlov, V.V., and Neishtadt, A.I. (2006). Mathematical Aspects of Classical and Celestial Me chanics. Springer-Verlag. 3rd Edition.
3. Bellman, R. (1970). Introduction to matrix analysis. Second edition. McGraw-Hill Book Co., New York-Diisseldorf-London.
4. Bernstein, G.M. and Liberman, M.A. (1989). A method for obtaining a canonical Hamiltonian for nonlinear LC circuits. IEEE Trans. Circuits Syst., 36, 411 –420.
5. Berstekas, D.P. (1996). Constrained optimization and La grange multiplier methods. Athena Scientific, Belmont, Massachusetts.