1. Amniotic fluid alphafetoprotein measurements in the early prenatal diagnosis of central nervous system disorders;Brock;Clin Genet,1975
2. Prenatal diagnosis of neural tube defects. III. A re-evaluation of the alpha-fetoprotein assay;Kimball;J Obstet Gynæcol,1977
3. Amniotic fluid alpha-fetoprotein levels and the prenatal diagnosis of neural tube defects: a collaborative study of 2180 pregnancies in the Netherlands;Kleijer;Br J Obstet Gynœcol,1978
4. Collaborative Study on Alpha-Fetoprotein in Relation to Neural-Tube Defects. Maternal serum alpha-fetoprotein measurement in antenatal screening for anecephaly and spina bifida in early pregnancy;Report of the U.K;Lancet,1977
5. Anencephalus, spina bifida and congential hydrocephalus: England and Wales 1964-1972;Rogers,1976