Wong A S W, Cheung G W Y, Manlulu Anthony V, Wan I, Chu Ming Chi, Yu Simon Ch, Tam Wing Hung, Yim Anthony
Department of Obstetrics and Gynecology, The Chinese University of Hong Kong, Hong Kong, China.
Acta Obstet Gynecol Scand. 2006;85(10):1273-5. doi: 10.1080/00016340600617940.