Carol Deppe’s books “Breed Your Own Vegetable varieties” and “the Resilient Gardener” are both awesome books that changed the way I garden forever!
https://www.chelseagreen.com/writer/carol-deppe/
https://www.amazon.com/stores/Carol-Deppe/author/B001K80VOQ
Along similar line, Steve Solomon - https://www.amazon.com/stores/Steve-Solomon/author/B001JRWZS8