1. Barnes PM , Powell-Griner E , McFann K , Nahin RL. Complementary and alternative medicine use among adults: United States, 2002. Adv Data. 2004;343:1–19.
2. Swerdlow JL. Modern Science Embraces Medicinal Plants. Nature’s Medicine: Plants that Heal. Washington, DC: National Geographic Society; 2000:110–57.
3. Swerdlow JL. Medicine Changes: late 19th to early 20th century. Nature’s Medicine: Plants that Heal. Washington, D.C.: National Geographic Society; 2000:158–91.
4. Barrett B , Kiefer D , Rabago D. Assessing the risks and benefits of herbal medicine: an overview of scientific evidence. Altern Ther Health Med. 1999;5:40–9.
5. Rotblatt M , Ziment I. Evidence-based herbal medicine. Philadelphia, PA: Hanley & Belfus; 2002.