1. Theorie und Anwendung der direkten Methode von Liapunov;Hahn,1959
2. Problème général de la stabilité du mouvement;Liapunov;Ann. Fac. Sci. Toulouse,1907
3. Kalman, R. E. and Bertram, J. E. Control system analysis and design via the ‘second method’ of Lyapunov. Pt 1—Continuoustime systems. J. Basic Engng, Trans. Amer. Soc. mech. Engrs No. 59-NAC-2
4. Kalman, R. E. and Bertram, J. E. Control system analysis and design via the ‘second method’ of Lyapunov. Pt 2—Discretetime systems. J. Basic Engng, Trans. Amer. Soc. mech. Engrs No. 59-NAC-3
5. Stability in Nonlinear Control Systems;Letov,1961