LARSSON, Kjell. Age and sex ratios of wintering Long-tailed Ducks Clangula hyemalis can be determined by analysis of photos of flying flocks at sea: A method description. Ornis Svecica, Lund, Sweden, v. 33, p. 1–20, 2023. DOI: 10.34080/os.v33.23757. Disponível em: https://journals.lub.lu.se/os/article/view/23757. Acesso em: 28 may. 2024.