Majewski Sharon, Donnenfeld Alan E, Kuhlman Kathleen, Patel Alpa
Center for Genetics, Fetal and maternal Medicine, Department of Obstetrics and Gynecology, Drexel University College of Medicine, Philadelphia, PA, USA.
J Ultrasound Med. 2007 Mar;26(3):391-5. doi: 10.7863/jum.2007.26.3.391.