Urinary levels of melatonin and risk of postmenopausal breast cancer: women's health initiative observational cohort.
Sturgeon SR, Doherty A, Reeves KW, Bigelow C, Stanczyk FZ, Ockene JK, Liu S, Manson JE, Neuhouser ML. Urinary levels of melatonin and risk of postmenopausal breast cancer: women's health initiative observational cohort. Cancer Epidemiol Biomarkers Prev. 2014 Apr; 23(4):629-37.