1. Reversible systems;Arnold,1984
2. Oscillations and bifurcations in reversible systems;Arnold,1986
3. Local Theory of Nonlinear Analytic Ordinary Differential Equations;Bibikov,1979
4. Multifrequency Nonlinear Oscillations and Their Bifurcations;Bibikov,1991
5. On the existence of invariant tori in a neighborhood of the zero solution of a system of ordinary differential equations;Bibikov;Diff. Eqs.,1967