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US Food and Drug Administration. Medication Guide Smallpox (Vaccinia) Vaccine, Live ACAM2000. Version 8.0, December 2015. http://www.fda.gov/downloads/BiologicsBloodVaccines/Vaccines/ApprovedProducts/UCM142576.pdf. Accessed March 2016.
Centers for Disease Control and Prevention. Emergency Preparedness and Response. Vaccine overview. http://www.bt.cdc.gov/agent/smallpox/vaccination/facts.asp. Updated February 22, 2016. Access March 2016.