Z. Getsova, A. Minkova, R. . Tsoneva, and K. Petkova, “EPIDEMIOLOGICAL COMPARISON OF INFLUENZA, ARI AND COVID-19 PREVALENCE IN BULGARIA FOR THE PERIOD 2017-2022”, Probl Infect Parasit Dis, vol. 51, no. 3, pp. 17–23, Jan. 2024, doi: 10.58395/nw1rvz88.