Enzymes: The Key to Health, by Howard F. Loomis Jr., D.C.
Enzyme Nutrition: The Food Enzyme Concept, by Edward Howell
Digestive Wellness, by Elizabeth Lipski, M.S., C.C.N
The Body Ecology Diet, by Donna Gates with Linda Schatz
I Was Poisoned by My Body, by Gloria Gilbere, N.D., D.A. Hom., Ph.D.