Risk factors affecting morbidity and mortality in patients with perforated peptic ulcers in sub‐Saharan Africa: A systematic review. Undergraduate Research in Health Journal, [S. l.], v. 1, n. 1, p. 7–11, 2023. Disponível em: https://samajournals.co.za/index.php/urhj/article/view/78. Acesso em: 29 apr. 2025.