ULLAH, A.; ULLAH, S.; ULLAH, A.; SADIQ, M. ud din; KHAN, M. FREQUENCY OF HELICOBACTER PYLORI IN PATIENTS PRESENTED WITH PERFORATED PEPTIC ULCER. Journal of Postgraduate Medical Institute, [S. l.], v. 21, n. 1, 2011. Disponível em: https://www.jpmi.org.pk/index.php/jpmi/article/view/142. Acesso em: 3 may. 2024.