Surjono, E., A. Firmansyah, and J. Batubara. “Knowledge of Pediatrician on Gastroesophageal Reflux/gastroesophageal Reflux Disease in Children: A Preliminary Study”. Paediatrica Indonesiana, Vol. 50, no. 6, Oct. 2016, pp. 336-9, doi:10.14238/pi50.6.2010.336-9.