STOYANOVA, Rumyana. COMPARISON OF DIFFERENT WAVES DURING THE COVID-19 PANDEMIC – EXPIRIENCE FROM BULGARIA. KNOWLEDGE - International Journal , [S. l.], v. 52, n. 4, p. 415–418, 2022. Disponível em: https://ojs.ikm.mk/index.php/kij/article/view/5205. Acesso em: 15 jun. 2026.