P. L. Chalya, J. N. Mrema, G. Kisanga, F. Massaga, L. Washington, and W. Mahalu, “Diagnostic value of pneumoperitoneum on plain abdominal film in patients with suspected visceral perforation at Bugando Medical Centre, Mwanza, Tanzania”, Tanzania J Hlth Res, vol. 24, no. 1, pp. 1–10, Jan. 2023.