WIA GC 1930/1477
Heydenreich, Elisabeth to Bing, Gertrud 06/02/1930
WIA GC 1934-50 L/15
Bing, Gertrud to Lachmann, Claire 22/11/1935
Extremely detailed letter containing updates and news. Includes as follows: apologies for silence...
WIA GC/1929/1225
Bing, Gertrud to Heydenreich [Mrs.] 14/12/1929
thanks her for warm words of condolences; although Mrs. Heydenreich met Warburg only for a very...