Merilä, Juha. “Two Mixed Clutches of Blue Tits Parus Caeruleus and Collared Flycatchers Ficedula Albicollis”. Ornis Svecica 4, no. 4 (October 1, 1994): 188–189. Accessed May 28, 2025. https://journals.lub.lu.se/os/article/view/23022.