Bensch S, Lindström Åke. The age of young Willow Warblers Phylloscopus trochilus estimated from different stages of post-juvenile moult. Ornis Svec [Internet]. 1992 Jan. 1 [cited 2024 Nov. 22];2(1):23-8. Available from: https://journals.lub.lu.se/os/article/view/23081