Gottfried Köthe (left), Hagemann, Otto Toeplitz (right) in Bonn 1930
Konrad Jacobs, Erlangen, Copyright is MFO
CC BY-SA 2.0 de
Mathematisches Forschungsinstitut Oberwolfach, <a rel="nofollow" class="external free" href="https://opc.mfo.de/detail?photo_id=2252">https://opc.mfo.de/detail?photo_id=2252</a>