LINDSTRÖM, Åke; SVENSSON, Sören; GREEN, Martin; OTTVALL, Richard. Distribution and population changes of two subspecies of Chiffchaff Phylloscopus collybita in Sweden. Ornis Svecica, Lund, Sweden, v. 17, n. 3–4, p. 137–147, 2007. DOI: 10.34080/os.v17.22684. Disponível em: https://journals.lub.lu.se/os/article/view/22684. Acesso em: 20 apr. 2024.