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2. U.S. Department of Agriculture. Internet site: http://www.ers.usda.gov/Data/FATUS (Accessed March 19, 2006).
3. U.S. Department of Agriculture. Internet site: http://www.ers.usda.gov/publications/oce501/oce20051g.pdf (Accessed February 5, 2006).
4. Centers for Disease Control and Prevention. Department of Health and Human Services. Internet site: http://www.cdc.gov/flu/avian/gen-info/facts.htm (Accessed November 7, 2006).