1. Manual of Antenatal Pathology and Hygiene;Ballantyne,1904
2. Gastroschisis;Moore;Surgery,1953
3. Omphalocele (amniocele);Margulies;Am J Obstet Gynecol,1945
4. Somatic anomalies of the umbilicus and anterior abdominal wall;Hutchin;Surg Gynecol Obstet,1965