1. Recurrent abdominal pains: a field survey of 1000 school children;Apley;Arch Dis Child,1958
2. Adult outcomes of pediatric recurrent abdominal pain: preliminary results;Campo,1999
3. The tip of the iceberg: the prevalence of functional gastrointestinal disease in children;Nurko;J Pediatr,2009
4. Chronic pain syndromes in childhood: one trunk, many branches;Schechter,2014
5. A million-dollar work-up for abdominal pain: is it worth it?;Dhroove;J Pediatr Gastroenterol Nutr,2010