Juwanto, Juwanto, et al. “Diagnostic Value of Barium Esophagogram and Bernstein Test in Patients With Esophagitis”. The Indonesian Journal of Gastroenterology, Hepatology, and Digestive Endoscopy, vol. 2, no. 1, Jan. 2001, pp. 5-13, doi:10.24871/2120015-13.