LEVÄNEN, S. Lufttemperaturens frekvens i Helsingfors åren 1882—91. Fennia - International Journal of Geography, [S. l.], v. 9, n. 1, p. 1–10, 1894. Disponível em: https://fennia.journal.fi/article/view/157148. Acesso em: 24 feb. 2025.