Authors: N J Leschot; H Wolf; A C Van Prooijen-Knegt; C J van Asperen; M Verjaal; G H Schuring-Blom; K Boer; H H Kanhai; G C Christiaens Journal: Br J Obstet Gynaecol Date: 1989-06
Authors: N J Wald; H S Cuckle; J W Densem; K Nanchahal; P Royston; T Chard; J E Haddow; G J Knight; G E Palomaki; J A Canick Journal: BMJ Date: 1988-10-08