Boev, Zlatozar. “Past Distribution of the White-Tailed Eagle (Haliaeetus Albicilla (Linnaeus, 1758)) in Bulgaria – Subfossil Record”. Proceedings of the Bulgarian Academy of Sciences 77, no. 5 (May 25, 2024): 669–675. Accessed January 19, 2025. https://proceedings.bas.bg/index.php/cr/article/view/535.