BIERNACKA-LUBAŃSKA, Małgorzata. From research on the topography and systematics of Roman defensive fortifications in the area of present-day Bulgaria. Balcanica Posnaniensia. Acta et studia, [S. l.], v. 5, p. 341–358, 1990. DOI: 10.14746/bp.1990.5.26. Disponível em: https://pressto.amu.edu.pl/index.php/bp/article/view/52705. Acesso em: 8 aug. 2026.