TY  - RPRT
TI  - Factors associated with multiple-pass procedures during chorionic villus sampling: a video analysis.
AU  - R K Silver
AU  - S N MacGregor
AU  - E D Hobart
PY  - 1992
DO  - 10.1002/pd.1970120307
UR  - https://pubmed.ncbi.nlm.nih.gov/1589420/
ID  - 1589420
ER  -