Karadeniz, R. S., Altay, M., Karasu, Y., Gelişen, O., & Haberal, A. (2009). Comparison of Triple and Qadrupple Test in Second Trimester Down Syndrome Screening. Gynecology Obstetrics &Amp; Reproductive Medicine, 15(1), 4–7. Retrieved from https://www.gorm.com.tr/index.php/GORM/article/view/372