Romieu I, Berlin J, et al. Oral contraceptives and breast cancer. Oral contraceptives and risk of breast cancer in women ages 20-54 years. 34 Weinstein A, Mahoney M, et al. Palmer J, Rosenberg L, et al.
Oral contraceptives use and breast cancer risk among African-American women.
Cancer Causes and Control. J of Cancer. 33 Wang Q, Ross R, et al. A case-control study of breast cancer in Tianjin, China. American Journal of Epidemiology.