1. Andorsky MB Vomiting. In: Rudolph AM ed. Pediatrics 18th ed. Appleton & Prentice Hall International Inc. 1987:902-3.
2. Silverman A. , Roy CC Pediatric clinical gastroenterology 3rd ed. C.V. Mosby Co. St. Louis, Toronto, London , 1983:10-11.
3. Lebenthal E. Textbook of gastroenterology and nutrition in infancy. Raven Press, New York , 1983:898-906.
4. Milla PJ, Muller Dpq. Harries pediatric gastroenterology 2nd ed. Churchill Livingstone, 1988:296,318-48,518.
5. Secretory otitis media in childhood