1. World Health Organization. Initiative for vaccine research: measles. Available at: www.who.int/vaccine_research/diseases/measles/en. Accessed April 12,2005
2. Centers for Disease Control and Prevention. Epidemiology of measles—United States, 2001–2003. MMWR Morb Mortal Wkly Rep.2004;53:713–716
3. Centers for Disease Control and Prevention. National, state, and urban area vaccination levels among children aged 19–35 months—United States, 2003. MMWR Morb Mortal Wkly Rep.2004;53:658–661
4. Centers for Disease Control and Prevention. State Immunization Requirements 2001–2002. Atlanta, GA: US Department of Health and Human Services, Centers for Disease Control and Prevention;2002
5. Centers for Disease Control and Prevention, National Vaccine Advisory Committee. Report of the NVAC Working Group on Philosophical Exemptions, Minutes of the National Vaccine Advisory Committee, January 13, 1998. Atlanta, GA: National Vaccine Program Office;1998:1–5