The Topology of Chaos, https://www.amazon.com/Topology-Chaos-Alice-Stretch-Squeezeland/dp/3527410678/ https://www.amazon.com/Topology-Chaos-Alice-Stretch-Squeez

The Topology of Chaos, https://www.amazon.com/Topology-Chaos-Alice-Stretch-Squeezeland/dp/3527410678/ https://www.amazon.com/Topology-Chaos-Alice-Stretch-Squeezel... is a good modern book on it. It is a fun problem because it stems from continuous diff eq but the answers come from topological analysis around the fixed sets, and the ways fixed sets can change as continuous parameters change.