BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Weißenborn, Wilhelm Dating: 10.02.1890
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Weißenborn, Wilhelm Dating: 03.11.1890
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Weißenborn, Wilhelm Dating: 10.11.1890