Friedman, L. M., Furberg. Curt, & DeMets, D. L. (1996). Fundamentals of clinical trials (3rd ed.). Mosby-Year Book.

Friedman, Lawrence M., Furberg. Curt, and David L. DeMets. Fundamentals of Clinical Trials. 3rd ed. St. Louis: Mosby-Year Book, 1996.

Friedman, Lawrence M., et al. Fundamentals of Clinical Trials. 3rd ed. Mosby-Year Book, 1996.