Duque, Edgar, Teresa Aristizábal, and Rosa Liliana Restrepo. “Serological Markers of Hepatitis B (AgHBs and Anti HBs) in High-Risk Individuals”. Colombia Medica 19, no. 3 (September 30, 1988): 98–101. Accessed May 21, 2025. https://colombiamedica.univalle.edu.co/index.php/comedica/article/view/6218.