Adaptedness of the Willow Tit Parus montanus to the migratory habit

Tiainen, J. (1980). Adaptedness of the Willow Tit Parus montanus to the migratory habit. Ornis Fennica, 57(2), 77–81. Noudettu osoitteesta https://ornisfennica.journal.fi/article/view/133037