Dr. Joel Fuhrman (2011). “Super Immunity: The Essential Nutrition Guide for Boosting Your Body's Defenses to Live Longer, Stronger, and Disease Free”, p.4, Harper Collins
Andrew Weil (2004). “Natural Health, Natural Medicine: The Complete Guide to Wellness and Self-Care for Optimum Health”, p.212, Houghton Mifflin Harcourt
Andrew Weil (2004). “Natural Health, Natural Medicine: The Complete Guide to Wellness and Self-Care for Optimum Health”, p.212, Houghton Mifflin Harcourt