Periconceptional Folate Intake by Supplement and Food Reduces the Risk of Nonsyndromic Cleft Lip With or Without Cleft Palate - van Rooij, I A; Ocke, M C; Straatman, H; Zielhuis, G A; Merkus, H M; Steegers-Theunissen, R P (Prev Med, 2004)