TY - JOUR T1 - Neural tube defects and periconceptional folic acid JF - Canadian Medical Association Journal JO - CMAJ SP - 255 LP - 256 VL - 167 IS - 3 AU - Rezan A. Kadir AU - Demetrios L. Economides Y1 - 2002/08/06 UR - http://www.cmaj.ca/content/167/3/255.abstract ER -