-
Fetal right ventricular contraction and relaxation times at 11-13 weeks' gestation by speckle tracking imaging.
Persico N, Fabietti I, Baffero G, Fedele L, Nicolaides KH.
Ultrasound Obstet Gynecol 2014;43:284-90. pdf -
Prenatal diagnosis of trisomy 18 at the 10-14-week ultrasound scan.
Sherod C, Sebire NJ, Soares W, Snijders RJ, Nicolaides KH.
Ultrasound Obstet Gynecol 1997;10:387-90.