The "early state" and its main characteristics. Research Announcements "Heritage BG", [S. l.], n. 7, p. 14–19, 2025. DOI: 10.58894/AR-HBg.2024.7.14-19. Disponível em: https://periodicals.uni-sofia.bg/index.php/AR-NBg/article/view/1207. Acesso em: 10 mar. 2026.