@article{9739a7e9611642b69a9d5a83dc9906fa,
title = "Screen-positive for Trisomy 21 at combined first trimester screening: how many do not have a prenatal karyotype?",
author = "Petersen, {Olav Bj{\o}rn} and Ida Vogel and J Hyett and Ekelund, {Charlotte Kvist} and Ann Tabor",
year = "2014",
month = sep,
doi = "10.1002/uog.13485",
language = "English",
volume = "44",
pages = "9",
journal = "Ultrasound in Obstetrics & Gynecology",
issn = "0960-7692",
publisher = "JohnWiley & Sons Ltd",
number = "Suppl. 1",
}