Jäntti, A., J. Suhonen, M. Kuitunen, ja T. Aho. 2003. ”Nest Defence of Eurasian Treecreeper Certhia Familiaris Against the Great Spotted Woodpecker Dendrocopos Major: Only One Parent Is Needed”. Ornis Fennica 80 (1):31–37. https://ornisfennica.journal.fi/article/view/133589.