Aijaz, Javeria, Fouzia Naseer, Maqboola Dojki, and Saba Jamal. “Duration of Respiratory Sample Stability at -80ºC for SARS-CoV-2 PCR”. Pakistan Journal of Medical Sciences 38, no. ICON-2022 (December 15, 2021). Accessed April 27, 2024. https://pjms.org.pk/index.php/pjms/article/view/5777.