1. Asymptotic Methods in the Theory of Nonlinear Oscillations;Bogolyubov,1963
2. Asymptotic solutions of analytic Hamiltonian systems;Cherry;J. Differential Equations,1968
3. An example of bifurcation to homoclinic orbits;Chow;J. Differential Equations,1980
4. Stability and Asymptotic Behavior of Differential Equations;Coppel,1965
5. Dichotomies in Stability Theory;Coppel,1978