WIA GC 1930/488
Bing, Gertrud to Brockhaus, Heinrich 16/04/1930
WIA GC 1930/489
Brockhaus, Heinrich to Bing, Gertrud 18/04/1930
WIA GC 1930/490
KBW to Brockhaus, Heinrich 24/04/1930
WIA GC 1931/2467
Proctor, Grete to Bing, Gertrud 08/06/1931
thanks for her letter in which Bing pointed to the fact that there are a number of mistakes in...
WIA GC 1931/289
Bing, Gertrud to Brockhaus, Heinrich 24/02/1931