Safety and efficacy of black cohosh and red clover for the management of vasomotor symptoms: a randomized controlled trial.
Geller SE, Shulman LP, van Breemen RB, Banuvar S, Zhou Y, Epstein G, Hedayat S, Nikolic D, Krause EC, Piersen CE, et al. Menopause. 2009 Nov-Dec; 16(6):1156-66.