1. Possible prevention of neural tube defects by periconceptionl vitamin supplementation;Smithells, R.W.; Sheppard, S.; Schorah, C.J.;Lancet,1980
2. Apparent prevention of neural tube defects by periconceptional vitamin supplementation;Smithells, R.W.; Sheppard, S.; Schorah, C.J.;Arch Dis Child,1981
3. Further experience of vitamin supplementation for prevention of neural tube defect recurrences;Smithells, R.W.; Seller, M.J.; Harris, R.;Lancet,1983
4. Prevention of neural tube defect recurrences in Yorkshire: fmal report;Smithells, R.W.; Sheppard, S.; Wild, J.; Schorah, C.J.;Lancet,1989
5. Double-blind randomised controlled trial of folate treatment before conception to prevent recurrence of neural-tube defects;Laurence, K.M.; James, N.; Miller, M.H.; Tennant, G.B.; Campbell, H.;BMJ,1981