Saeed, A., Kalfah, A., & Mohammed, Z. (2023). Comparing the accuracy of nasopharyngeal COVID-19 PCR alone versus combined nasopharyngeal and oropharyngeal COVID-19 PCR tests. International Journal of Research in Medical Sciences, 11(11), 3969–3975. https://doi.org/10.18203/2320-6012.ijrms20233363