ÅSTRÖM, Gustav; STOLT, Bengt-Olov. Regional song dialects of the Ortolan Bunting Emberiza hortulana L. in Sweden. Ornis Svecica, Lund, Sweden, v. 3, n. 1, p. 1–10, 1993. DOI: 10.34080/os.v3.23047. Disponível em: https://journals.lub.lu.se/os/article/view/23047. Acesso em: 1 jul. 2024.