Food of the Gods by Terrence McKenna (https://www.penguinrandomhouse.com/books/111941/food-of-the-...)
How to Change Your Mind by Michael Pollan (https://www.penguinrandomhouse.com/books/529343/how-to-chang...)
Fellowship of the River by Joe Tafur, MD (https://www.drjoetafur.com/the-fellowship-of-the-river)