KARLSSON, L.; PERSSON, K.; WALINDER, G. Ageing of Tree Pipits Anthus t. trivialis. Ornis Svecica, Lund, Sweden, v. 3, n. 2, p. 69–80, 1993. DOI: 10.34080/os.v3.23045. Disponível em: https://journals.lub.lu.se/os/article/view/23045. Acesso em: 6 jul. 2022.