1. Vibration Theory;Andronov,1959
2. Stability of the equilibrium positions in relay systems;Anosov;Autom. Remote Control,1959
3. On the number of limit cycles which appear with the variation of coefficients from an equilibrium position of focus or center type;Bautin;Mat. Sb. (NS),1952
4. Degenerate Hopf bifurcation in discontinuous planar systems;Coll;J. Math. Anal. Appl.,2001
5. Piecewise-Smooth Dynamical Systems, Theory and Applications;di Bernardo,2008