References
- Eisenberg D M, Davis R B, Ettner S L, et al. Trends in alternative medicine use in the United States, 1990–1997. Results of a follow-up national survey. JAMA 1998; 280: 1569–75
- Kessler R C, Davis R B, Foster D F, et al. Long-term trends in the use of complementary and alternative medical therapies in the United States. Ann Intern Med 2001; 135: 262–268
- WHO Monographs on Selected Medicinal Plants, Volume 1. World Health Organization, Geneva 1999
- Herbal Medicine: Expanded Commission E Monographs, M Blumenthal, A Goldberg, J Brinckmann. Integrative Medicine Communications, Newton, MA 2000
- Robbers J E, Tyler V E. Tyler's Herbs of Choice: The Therapeutic Use of Phytomedicinals. The Haworth Herbal Press, New York 1999