Atanasov, Teodor D., Katya T. Todorova, and Alexandar I. Tsvetanov. “Spontaneous Retroperitoneal Hematoma in COVID-19 Patients”. International Surgery Journal 9, no. 8 (July 26, 2022): 1464–1469. Accessed November 10, 2025. https://www.ijsurgery.com/index.php/isj/article/view/8930.