Youssef A, Pilu G
Department of Obstetrics and Gynecology, University of Bologna and Bologna University Hospital Sant'Orsola-Malpighi, Via Massarenti, 13, Bologna, 40138, Italy.
Ultrasound Obstet Gynecol. 2016 Apr;47(4):523-4. doi: 10.1002/uog.15874.