Helminen M. Occurrence of the Red-flanked Bluetail (Tarsiger cyanurus) in Finland and some remarks concerning its expansion to the west. Ornis Fenn [Internet]. 30 september 1958 [citerad 18 maj 2024];35(2–3):51–64. Tillgänglig vid: https://ornisfennica.journal.fi/article/view/132621