Hello, I recently bought the book "101st Airborne, Ecussons - Patches" written by Kevin Delaître (with introduction by Mark A. Bando). This book can be purchased directly from the author (through his facebook), its cost is 20 euros and he sends it to any country.
It has a large number of photos and helps you identify the types of patches of the 101st airborne. I recommend it.

José