STOYANOVA, A.; BERBEROVA, R. Data analysis of the mid-winter census of wintering aquatic birds on the territory of Ramsar sites along the Bulgarian Black Sea coast for the period 2012 – 2021. Annual of Natural Sciences Department, [S. l.], v. 8, p. 8–19, 2023. DOI: 10.33919/ansd.23.8.2. Disponível em: https://ojs.nbu.bg/index.php/ANSD/article/view/1123. Acesso em: 6 jun. 2025.