A new contact zone in the Chiffchaff distribution range: Caucasian and European subspecies meet each other in the south of Russia. Ornis Fennica, [S. l.], v. 101, n. 1–2, p. 16–27, 2024. DOI: 10.51812/of.131719. Disponível em: https://ornisfennica.journal.fi/article/view/131719. Acesso em: 6 nov. 2025.