A comparative multicenter study of the effects of continuous low-dose estradiol released from a new vaginal ring versus estriol vaginal pessaries in postmenopausal women with symptoms and signs of urogenital atrophy - Henriksson,L.; Stjernquist,M.; Boquist,L.; Alander,U.; Selinus,I. (Am J Obstet Gynecol, 1994)