NILSSON, L.; PIRKOLA, M. K. Migration pattern of Finnish Bean Geese Anser fabalis. Ornis Svecica, Lund, Sweden, v. 1, n. 2, p. 69–80, 1991. DOI: 10.34080/os.v1.23085. Disponível em: https://journals.lub.lu.se/os/article/view/23085. Acesso em: 17 aug. 2022.