Wallraff, Hans Georg Verhaltensphysiologie, Seewiesen, Max Planck Institut für Ornithologie, Max Planck Society;
Foa, A., Benvenuti, S., Ioale, P., & Wallraff, H. G. (1984). Geographical and temporal variability in pigeon homing. Parallel studies in Italy and Germany. Behavioral Ecology and Sociobiology, 15(1), 25-34. doi:10.1007/bf00310211.