ХАБУРГАЕВ, Г. А. The Reform of Old Slavonic in Preslav School of Simeon. Kalbotyra, [S. l.], v. 39, n. 2, p. 4–12, 1988. Disponível em: https://test.zurnalai.vu.lt/kalbotyra/article/view/31059. Acesso em: 27 oct. 2025.