Reference
Elzbieta Fuszara, Maciej Fuszara, Michal Wojciechowski (2002): Wintering of the Barbastelle, Barbastella barbastellus, in fortifications of the Masurian Lake District (Poland) – Nyctalus – Internationale Fledermaus-Fachzeitschrift – NF_8: 536 - 540.