1. Bacciotti, A. (1992) Linear feedback: the local and potentially global stabilization of cascade systems, Proc. 2nd IFAC Symp. Nonlinear Control Systems Design, 21–25.
2. Birkhoff, G. D. (1968) Collected Mathematical Papers, Dover, Vol. 2.
3. Brocket, R. W. (1983) Asymptotic stability and feedback stabilization, Differential Geometric Control Theory, R.W. Brockett, R.S. Millmann, H.J. Sussmann, eds., Birkhäuser, Boston, 181–191.
4. Brockett, R. W., Byrnes, C. I. (2000) The geometry of periodic orbits with applications to nonlinear control systems, Preprint Department of Systems Science and mathematics, Washington University, St. Louis.
5. Byrnes, C. I., Isidori, A. (1984) ‘A Frequency Domain Philosophy for Nonlinear Systems, with Applications to Stabilization and to Adaptive Control', Proc. of 23rd IEEE Conf. on Decision and Control, Las Vegas.