Balch, Phyllis, CNC. Perscription for Nutritional Healing, 5th ed., Published by the Penguin Group, 2010
Sierpina, Victor, MD, ABFP, ABHM; Espinosa, Geovanni, ND, LAc, RH(AHG). 1000 Cures for 200 Ailments, 1st 3d., HarperCollins Publishers, 2007
Smith, Pamela MD, MPH. Vitamins Minerals Herbs and So Much More, 2nd ed., Square One Publishers, 2020
Dietary Supplement Fact Sheets. National Institutes of Health, Office of Dietary Supplements on their website.