GRENQVIST, P. Muscicapa parva (Bechst.) och Sylvia nisoria (Bechst.) i Kökar, Åland. Ornis Fennica, [S. l.], v. 8, n. 3–4, p. 84–88, 1931. Disponível em: https://ornisfennica.journal.fi/article/view/132271. Acesso em: 17 may. 2024.