1. Dynamical Systems I;Anosov,1988
2. Geometric Methods in Theory of Ordinary Differential Equations;Arnold,1988
3. One-Dimensional Functional Equations;Belitskii,2003
4. A functional equation for the embedding of a homeomorphism of the interval into a flow;Beyer,1985
5. Local Theory of Nonlinear Analytic Ordinary Differential Equations;Bibikov,1979