1. C. I. Byrnes. “Toward a global theory of (f, g)—invariant distributions with sin gularities,” in Mathematical Theory of Networks and, Systems, Proceedings of the MTNS-83 International Symposium, Beer-Sheba, Israel, 1983 (P. A. Fuhrmann, Ed.), Springer-Verlag, New York, NY, 1984, pp. 149–165.
2. C. I. Byrnes and A. J. Krener. “On the existence of globally (f, g)— invariant dis tributions,” in Differential Geometric Control Theory (R. W. Brockett, R. S. Millman, H. J. Sussmann, Eds.), Birkhäuser, Boston, MA, 1983, pp. 209–225.
3. C. Chevalley. Theory of Lie Groups, Princeton Univesity Press, Princeton, NJ, 1946.
4. D. Cheng and T. J. Tarn. “New result on (f, g) — invariance,” Systems Control Lett., 12(1989), pp. 319–326.
5. W. Dayawansa, D. Cheng, W. M. Boothby, and T. J. Tarn. “On the global (f, g)—invariance of a class of nonlinear systems” in Proceedings of the 25th IEEE Conference on Decision and Control, IEEE Control Systems Society, 1986, pp. 2065–2068.