English
Reference
Jürgen Haffer, Ernst Mayr (1997): "We must lead the way on new paths" The work and correspondence of Hartert, Stresemann, Ernst Mayr - international ornithologists Ornithologen-Briefe des 20. Jahrhunderts – Ökologie der Vögel. Verhalten Konstitution Umwelt – 19: 1 - 980.
