Velasco-Benítez, C. A., Calderón-Guerrero, O. G., & Ramírez-Villamizar, J. (2019). Functional gastrointestinal disorders in schoolchildren with chronic abdominal pain in a pediatric digestive endoscopy unit. Universidad Y Salud, 22(1), 52–57. https://doi.org/10.22267/rus.202201.174