A Brief History of Bulgaria from the Fırst Bulgarian State to the Principality of Bulgaria. ESAR Journal, [S. l.], v. 3, n. 1, p. 94–101, 2022. DOI: 10.5281/zenodo.13248117. Disponível em: https://www.esarjournal.com/index.php/ESAR/article/view/32.. Acesso em: 11 nov. 2026.