Madzharova, Iveta, Ivelina Tifonova, Veselin Dobrinov, Iliyana Grigorova, Ivailo Alexiev, Lubomira Grigorova, Reneta Dimitrova, et al. 2023. “Dynamic of SARS-CoV-2 Spread in Bulgaria, 2020-2022”. PROBLEMS of Infectious and Parasitic Diseases 51 (1): 5-10. https://doi.org/10.58395/68gqp351.