BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Jensen, Wilhelm Dating: 15.04.1883
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Jensen, Wilhelm Dating: 23.07.1883
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Jensen, Wilhelm Dating: 08.07.1887
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Jensen, Wilhelm Dating: 03.03.1894
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Jensen, Wilhelm Dating: 20.02.1894