APA

Li H., Schut H. A., Conran P., Kramer P. M., Lubet R. A., Steele V. E., Hawk E. E., Kelloff G. J. & Pereira M. A. (19990413). Prevention by aspirin and its combination with alpha-difluoromethylornithine of azoxymethane-induced tumors, aberrant crypt foci and prostaglandin E2 levels in rat colon. : Carcinogenesis.

Chicago

Li H, Schut H A, Conran P, Kramer P M, Lubet R A, Steele V E, Hawk E E, Kelloff G J and Pereira M A. 19990413. Prevention by aspirin and its combination with alpha-difluoromethylornithine of azoxymethane-induced tumors, aberrant crypt foci and prostaglandin E2 levels in rat colon. : Carcinogenesis.

Harvard

Li H., Schut H. A., Conran P., Kramer P. M., Lubet R. A., Steele V. E., Hawk E. E., Kelloff G. J. and Pereira M. A. (19990413). Prevention by aspirin and its combination with alpha-difluoromethylornithine of azoxymethane-induced tumors, aberrant crypt foci and prostaglandin E2 levels in rat colon. : Carcinogenesis.

MLA

Li H, Schut H A, Conran P, Kramer P M, Lubet R A, Steele V E, Hawk E E, Kelloff G J and Pereira M A. Prevention by aspirin and its combination with alpha-difluoromethylornithine of azoxymethane-induced tumors, aberrant crypt foci and prostaglandin E2 levels in rat colon. : Carcinogenesis. 19990413.