Pulliainen, E., P. Helle, and P. Tunkkari. “Adaptive Radiation of the Digestive System, Heart and Wings of Turdus Pilaris, Bombycilla Garrulus, Sturnus Vulgaris, Pyrrhula Pyrrhula, Pinicola Enucleator and Loxia Pytyopsittacus”. Ornis Fennica 58, no. 1 (March 31, 1981): 21–28. Accessed November 23, 2024. https://ornisfennica.journal.fi/article/view/133059.