Johannes CB, Crawford SL. Menstrual bleeding, hormones, and the menopausal transition. Semin Reprod Endocrinol. 1999 Jan 1;17(4):299-309.
Clarkson T, Anthony MS, Hughes C. Estrogenic soybean isoflavones and chronic disease: risks and benefits. Trends Endocrinol Metab. 1995 Jan;6(1):11-6.