Hromada, M., Kuczynski, L., Krištín, A., & Tryjanowski, P. (2003). Animals of different phenotype differentially utilise dietary niche- the case of the Great Grey Shrike Lanius excubitor. Ornis Fennica, 80(2), 71–78. Retrieved from https://ornisfennica.journal.fi/article/view/133594