1. Bifurcation of a periodic solution from a stationary solution of a system of differential equations;Hopf,1942
2. Bifurcation of a periodic solution from a stationary solution of a system of differential equations;Hopft;Berrichten der Mathematische Physikalische Klasses der Sachiren Acad. Wissenschaften,1942
3. Theory and applications of Hopf bifurcation;Hassard,1981
4. The Hopf bifurcation and its applications;Marsden,1976
5. Ordinary differential equations;Hale,1969