Shih J C, Tsao P N, Huang S F, Yen B L, Lin J H, Lee C N, Hsieh F J
Department of Obstetrics and Gynecology, College of Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Ultrasound Obstet Gynecol. 2000 Jul;16(1):103. doi: 10.1046/j.1469-0705.2000.00171.x.