BARTONIKA, Tomáš and Zdeněk ŘEHÁK. Variability in echolocation calls of Pipistrellus pygmaeus (Chiroptera: Vespertilionidae) during search flight in different habitats.
Acta Theriologica. Polsko: Mammal Research Institute, Polish Academy of Sciences, 2005, 50/2005, No 2, p. 145-160. ISSN 0001-7051.