Ulfvens, J. “Offshore Breeding in the Great Crested Grebe Podiceps Cristatus: Two Offshore Areas Examined in Relation to an Inshore Area in Western Finland”. Ornis Fennica 66, no. 3 (September 30, 1989): 112–116. Accessed November 22, 2024. https://ornisfennica.journal.fi/article/view/133284.