Janiga, M., and Z. Višňovská. “The Placement and the Size and Shape of Nests of Ring Ouzel (Turdus Torquatus) Reflect the Environmental Conditions at Different Altitude”. Oecologia Montana 13, no. 1-2 (December 1, 2004): 11-16. Accessed August 18, 2019. https://om.vuvb.uniza.sk/index.php/OM/article/view/173.