TY  - RPRT
TI  - First trimester screening: the BUN study.
AU  - Ronald J Wapner
PY  - 2005
DO  - 10.1053/j.semperi.2005.05.013
UR  - https://pubmed.ncbi.nlm.nih.gov/16104674/
ID  - 16104674
ER  -