Reference:
- Embryology, Anatomy, and Diseases of the Umbilicus: Together with Diseases of the Urachus, 1st ed, Cullen TS (Ed), W.B. Saunders Company, Philadelphia 1916.
Modified from: Cilley R. Disorders of the umbilicus. In: Pediatric Surgery, Grosfeld J, O'Neill J, Coran A, Fonkalsrud E (Eds), Mosby Inc., Philadelphia 2006.
