KARASU, Zeki, et al. “Predictive Value of Proliferating Cell Nuclear Antigen Index in Response to Interferon Treatment in Patients With Chronic Viral Hepatitis B and C”. Turkish Journal of Gastroenterology, vol. 12, no. 2, Jan. 2001, pp. 89-94, https://turkjgastroenterol.org/index.php/tjg/article/view/1133.