1. Antenatal diagnosis of neural tube defects in Canada: extension of a collaborative study;Simpson;Can. Med. Assoc. J.,1979
2. Maternal serum alpha-fetoprotein measurement in antenatal screening for anencephaly and spina bifida in early pregnancy;Lancet,1977
3. Antenatal misdiagnosis of neural tube defects;Brock;Lancet,1975
4. The molecular nature of alpha-fetoprotein in anencephaly and spina bifida;Brock;Clin. Chim. Acta,1974
5. 5.