Fareniy, I. A. “The Settlements of the Coal Tits (Parus Ater) in the Artificial Nest Boxes Near the Suburbs of the Sokyrno Village in Cherkasy Region and Oblast”. Cherkasy University Bulletin: Biological Sciences Series, no. 1, Mar. 2016, pp. 104-10, https://bio-ejournal.cdu.edu.ua/article/view/622.