KARAGAS, MARGARET R., MARTIN A. WEINSTOCK, and HEATHER H. NELSON. "Keratinocyte Carcinomas (Basal and Squamous Cell Carcinomas of the Skin)." Cancer Epidemiology and Prevention. : Oxford University Press, 2006-10-12. Oxford Scholarship Online. 2009-09-01. Date Accessed 25 May. 2013 <http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780195149616.001.0001/acprof-9780195149616-chapter-64>.
KARAGAS, M., WEINSTOCK, M., & NELSON, H.(2006-10-12). Keratinocyte Carcinomas (Basal and Squamous Cell Carcinomas of the Skin). In Cancer Epidemiology and Prevention. : Oxford University Press. Retrieved 25 May. 2013, from http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780195149616.001.0001/acprof-9780195149616-chapter-64.
KARAGAS, MARGARET R., MARTIN A. WEINSTOCK, and HEATHER H. NELSON. "Keratinocyte Carcinomas (Basal and Squamous Cell Carcinomas of the Skin)." In Cancer Epidemiology and Prevention. : Oxford University Press, 2006-10-12. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780195149616.001.0001/acprof-9780195149616-chapter-64.
KARAGAS MR, WEINSTOCK MA, NELSON HH. Keratinocyte Carcinomas (Basal and Squamous Cell Carcinomas of the Skin). In: Schottenfeld D, Fraumeni JF. Cancer Epidemiology and Prevention. Oxford University Press; 2006. http://www.oxfordscholarship.com/view/10.1093/acprof:oso/9780195149616.001.0001/acprof-9780195149616-chapter-64. Accessed May 25, 2013.