Maternal serum screening for Down's syndrome in early pregnancy.
Wald NJ, Cuckle HS, Densem JW, Nanchahal K, Royston P, Chard T, Haddow JE, Knight GJ, Palomaki GE, Canick JA.
Wald NJ, et al.
BMJ. 1988 Oct 8;297(6653):883-7. doi: 10.1136/bmj.297.6653.883.
BMJ. 1988.
PMID: 2460174
Free PMC article.