OMER MOHAMMED, F., and S. HASAN ALI. “SPECTRUM OF UNENHANCED CT-CHEST APPEARANCES AND SEVERITY IN COVID 19 PATIENTS IN DUHOK, KURDISTAN REGION, IRAQ”. Duhok Medical Journal, Vol. 17, no. 2, Dec. 2023, pp. 21-31, https://dmj.uod.ac/index.php/dmj/article/view/257.