BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Heldburg, Helene Freifrau von Dating: 16.02.1904
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Heldburg, Helene Freifrau von Dating: 21.03.1904
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Heldburg, Helene Freifrau von Dating: 01.04.1904