1. Application of methods of nonlinear mechanics in the theory of steady oscillations;Krylov,1934
2. On small periodic perturbations of autonomous systems;Afraimovich;Dokl. Akad. Nauk SSSR,1974
3. On certain combined bifurcations associated with the disappearance of a stationary point of the saddle-node kind;Afraimovich;Dokl. Akad. Nauk SSSR,1974
4. Theory of dynamic system bifurcation and dangerous boundaries;Shil'nikov;Dokl. Akad. Nauk SSSR,1975
5. The Theory of Bifurcation of Dynamic Systems in a Plane;Andronov,1967