NYSTRÖM, E. Iakttagelser över mindre korsnäbben (Loxia curvirostra L). Ornis Fennica, [S. l.], v. 2, n. 1, p. 8–13, 1925. Disponível em: https://ornisfennica.journal.fi/article/view/132125. Acesso em: 13 may. 2024.