TITLE: Problem books in ODE
QUESTION [5 upvotes]: I'm studying Ordinary differential equations right now in the level of Hartman's book.
I've never seen problem books in ODE in this level even if you consider it without solutions.
I would like to know if one of you know any problem book in ODE in this level?
Thanks a lot

REPLY [2 votes]: I do not know of another book like this one.
I think you can do several things, like finding books with the main themes, for example:

Example 1: About Exponential Dichotomy of Linear Autonomous Differential Equations, Mircea Reghis
Example 2: Perturbation Methods for Differential Equations, Bhimsen Shivamoggi
Example 3: Countable Systems of Differential Equations by A. M. Samoilenko, Yu. V. Teplinskii
Another Suggestion: Review the extensive list of references in his book and see other books on the main themes that he used, including the referenced papers