Bhattarai, A.; Jha, B.; Timilsina, S. Serum CA 19-9 Levels in Benign and Malignant Diseases Associated With the Gastrointestinal Tract. Ann. Clin. Chem. & Lab. Med. 2015, 1 (2), 35-41. https://doi.org/10.3126/acclm.v1i2.13546.