1. Baker, L. C., Bundorf, M. K., Singer, S. & Wagner, T. H. (2003). Validity of the survey of health and internet and knowledge network’s panel and sampling. Available: http://www.knowledgenetworks.com/ganp/docs/Appendix%20Survey%20of%20Health%20and%20the%20Internet.pdf.
2. Brabin, L., Roberts, S. A., Stretch, R., Baxter, D., Chambers, G., Kitchener, H., et al. (2008). Uptake of first two doses of human papillomavirus vaccine by adolescent schoolgirls in Manchester: Prospective cohort study. British Medical Journal, 336, 1056–1058.
3. Brener, N. D., Wheeler, L., Wolfe, L. C., Vernon-Smiley, M., & Caldart-Olson, L. (2007). Health services: Results from the school health policies and programs study 2006. Journal of School Health, 77, 464–485.
4. Brotherton, J. M., Deeks, S. L., Campbell-Lloyd, S., Misrachi, A., Passaris, I., Peterson, K., et al. (2008). Interim estimates of human papillomavirus vaccination coverage in the school-based program in Australia. Communicable Diseases Intelligence, 32, 457–461.
5. Centers for Disease Control and Prevention. (2010a). 2010 child and adolescent immunization schedules. Available: http://www.cdc.gov/vaccines/recs/schedules/child-schedule.htm.