BERGGREN, Lars. The northern Chiffchaff Phylloscopus collybita abietinus in crisis?. Ornis Svecica, Lund, Sweden, v. 9, n. 1–2, p. 86–90, 1999. DOI: 10.34080/os.v9.22920. Disponível em: https://journals.lub.lu.se/os/article/view/22920. Acesso em: 28 mar. 2024.