1. Congenital malformations and environmental influences in pregnancy;Richards IDG;Br J Prev Soc Med,1969
2. Hypothesis: anencephaly and spina bifida are usually preventable by avoidance of a specific but unidentified substance present in certain potato tubers;Renwick JH;Br J Prev Soc Med,1972
3. Anencephalus and dietary intakes;Knox EG;Br J Prev Soc Med,1972
4. Historical associations of congenital malformations