Schweitzer K J, van Bekkum E, de Groot C J M
Department of Obstetrics and Gynecology, Erasmus Medical Centre Rotterdam, Division of Obstetrics and Prenatal Medicine, Rotterdam, The Netherlands.
Int J Gynaecol Obstet. 2006 May;93(2):152-3. doi: 10.1016/j.ijgo.2006.01.022. Epub 2006 Mar 20.