1. Fletcher JM, Copeland K, Frederick JA, Blaser SE, Kramer LA, Northrup H, Hannay HJ, Brandt ME, Francis DJ, Villarreal G, Drake JM, Laurent JP, Townsend I, Inwood S, Boudousquie A, Dennis M (2005) Spinal lesion level in spina bifida: a source of neural and cognitive heterogeneity. J Neurosurg 102:268–279
2. Rothbart HB (1936) Lacunar skull of the new-born. Am J Dis Child 52:1375–1389
3. Feldkamp M, Sanchez E, Canfield M (2014) International Clearinghouse of Birth Defects Surveillance and Research–Annual Report 2014
4. Lammer EJ, Sever LE, Oakley GP Jr (1987) Valproic acid. Teratology 35:465–473
5. MRC Vitamin Study Research Group (1991) Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. Lancet 338:131–137