Bhattarai, Aseem, Bharat Jha, and Santosh Timilsina. “Serum CA 19-9 Levels in Benign and Malignant Diseases Associated With the Gastrointestinal Tract”. Annals of Clinical Chemistry and Laboratory Medicine 1, no. 2 (October 2, 2015): 35–41. Accessed April 19, 2024. https://www.nepjol.info/index.php/ACCLM/article/view/13546.