Efimova, Taisia A., Igor A. Timoshchenko, and Natalia G. Abrashina-Zhadaeva. 2021. “Fractional Differential Model of the Spread of COVID-19”. Journal of the Belarusian State University. Physics, no. 3 (October): 40-48. https://doi.org/10.33581/2520-2243-2021-3-40-48.