Wallraff, Hans Georg Verhaltensphysiologie, Seewiesen, Max Planck Institut für Ornithologie, Max Planck Society;
Wallraff, H. G. (2001). Navigation by homing pigeons: Updated perspective. Ethology, Ecology & Evolution, 13(1), 1-48. doi:10.1080/08927014.2001.9522786.