Tjernberg, M., Johnsson, K. and Nilsson, S. G. (1993) “Density variation and breeding success of the Black Woodpecker Dryocopus martius in relation to forest fragmentation”, Ornis Fennica, 70(3), pp. 155–162. Available at: https://ornisfennica.journal.fi/article/view/133377 (Accessed: 19May2024).