Al-noori, Aleen Sardar, Ahmed Mohamed Salih, and Muayad Aghali Merza. “Vaccination and Vitamin D in Relation to Disease Severity and Mortality in Patients With COVID-19 Disease: A Follow-up Study: COVID-19 Status, Its Vaccination, and Vitamin D”. Cellular and Molecular Biology 71, no. 11 (December 6, 2025): 100–108. Accessed December 6, 2025. http://mail.cellmolbiol.org/index.php/CMB/article/view/5922.