L. Husen, G. A. Siregar, and M. Lubis, “The Difference of Hypoxic Inducible Factor-1α, Vascular Endothelial Growth Factor, and Transforming Growth Factor-β1 Based on Liver Fibrosis Severity in Patients with Chronic Hepatitis B”, Open Access Maced J Med Sci, vol. 9, no. B, pp. 91–95, Jan. 2021.