A.-A. . Muhammed, “Covid-19 Vaccines, Countries around the World, and the Vaccines they are Currently Administering: A Practical Insight and Narrative Review”, IJSBAR, vol. 60, no. 2, pp. 162–174, Sep. 2021, Accessed: Oct. 12, 2025. [Online]. Available: https://www.gssrr.org/JournalOfBasicAndApplied/article/view/13231