“Variety of Antibody Responses to BNT162b2 and BBIBP-CorV Vaccinations Against COVID-19 Infections in Baghdad and Fallujah, Iraq”, UKHJSE, vol. 7, no. 1, pp. 17–25, Aug. 2023, doi: 10.25079/ukhjse.v7n1y2023.pp17-25.