WIA GC/1905/231
Herzfelder, Jacques to Warburg, Aby 11/09/1905
thanks him for his article on the imprese amorose
WIA GC/1906/312
Herzfelder, Jacques to Warburg, Aby and Warburg, Mary 30/06/1906
thanks them for their lovely present
WIA GC/1906/455
Magnus, Helene to Warburg, Aby 12/02/1906
on her appointment and meeting with Professor Adolf von Hildebrand in Munich; she has rented a...