HELLE, E.; HELLE, P.; VÄISÄNEN, R. A. Population trends among archipelago birds in the Krunnit sanctuary, northern Gulf of Bothina, in 1939–85. Ornis Fennica, [S. l.], v. 65, n. 1, p. 1–12, 1988. Disponível em: https://ornisfennica.journal.fi/article/view/133250. Acesso em: 17 may. 2024.