Jedrzejewska, B., and W. Jedrzejewska. “Summer Food of the Pygmy Owl Glaucidium Passerinum in Bialowieza National Park, Poland”. Ornis Fennica 70, no. 4 (December 31, 1993): 196–201. Accessed November 22, 2024. https://ornisfennica.journal.fi/article/view/133382.