References 909

Ziolkowska, Katarzyna, Piotr Dydowicz, Maciej Sobkowski, Kinga Tobola-Wrobel, Ewa Wysocka, Marek Pietryga. 2019. "The clinical usefulness of biochemical (free β-hCg, PaPP-a) and ultrasound (nuchal translucency) parameters in prenatal screening of trisomy 21 in the first trimester of pregnancy." Ginekologia Polska 90:161–166. https://doi.org/10.5603/GP.2019.0029