Renaldi, K. et al. 2020. Serum CA 19-9 of Pancreatic Solid Mass Patients in Dr. Cipto Mangunkusumo National Central General Hospital. The Indonesian Journal of Gastroenterology, Hepatology, and Digestive Endoscopy. 21, 3 (Dec. 2020), 188–192. DOI:https://doi.org/10.24871/2132020188-192.