1. US Department of Health & Human Services. Pandemic flu history. Flu.gov. Available from: http://www.flu.gov/pandemic/history/index.html. Accessed July 11, 2012.
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3. Statewide Planning and Research Cooperative System (SPARCS) (database). Albany [NY]: New York State Department of Health; 2007-2010. Available from: http://www.health.ny.gov/statistics/sparcs/. Accessed August 9, 2012.
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5. National Institute for Occupational Safety and Health. Respirator trusted-source information page. 2012. Available from: http://www.cdc.gov/niosh/npptl/topics/respirators/disp_part/RespSource.html. Accessed July 11, 2012.