1. Ultrasonic detection of an abnormal mass in a fetus later shown to have trisomy 18;Heller, R.H.; Adams, J.E.; Hirschfeld, R.L.; Tapper, A.J.;Prenatal Diagnosis,1980
2. Prenatal diagnosis of neural tube defects. Genetic disorders and the Jfets;Milunsky, A.,1979
3. Raised alpha-fetoprotein levels in amniotic fluid and maternal serum associated with distension of the fetal bladder by absence of the urethra;Nevin, N.C.; Ritchie, A.; McKeown, F.; Roberts, G.;J Med Genet,1978
4. Quantitative and qualitative assay of amniotic fluid acetylcholinesterase in prenatal diagnosis of neural tube defects;Voigtlander, T.; Friedl, W.; Cremer, M.; Schmidt, W.; Schroeder, T.M.;Hum Genet,1981
5. Report of the Collaborative Acetylcholinesterase Study. Amniotic fluid acetylcholinesterase electrophoresis as a secondary test in the diagnosis of anencephaly and open spina bifida in early pregnancy;Lancet,1981