Studies on the Antioxidant Activity of Echinacea Root ExtractChun Hu, David D. Kitts — Food, Nutrition and Health, Faculty of Agricultural Science, University of British Columbia, 6650 N.W. Marine Drive, Vancouver, BC, Canada V6T 1Z4 — 14 April 2000, 48 (5), pp. 1466–1472. DOI: 10.1021/jf990677+