Turner, VLG. (2002) Aspects of the ecology of Daubenton’s bat (Myotis daubentonii), the common pipistrelle (Pipistrellus pipistrellus), the soprano pipistrelle (P. pygmaeus) and their potential prey in relation to altitude. Ph.D. Thesis (Ecology & Acoustics). Department of Biology (University of Leeds) Leeds, UK, p. 250.