BRIEF OHNE UMSCHLAG Jensen, Wilhelm Author: Jensen, Wilhelm Recipient: Haeckel, Ernst Dating: 04.10.1882
BRIEF OHNE UMSCHLAG Jensen, Wilhelm Author: Jensen, Wilhelm Recipient: Haeckel, Ernst Dating: 02.04.1883
BRIEF OHNE UMSCHLAG Jensen, Wilhelm Author: Jensen, Wilhelm Recipient: Haeckel, Ernst Dating: 21.07.1883
BRIEF [O.A.] Ziegler, Heinrich Ernst Author: Ziegler, Heinrich Ernst Recipient: Haeckel, Ernst Dating: 10.11.1891
BRIEF [O.A.] Ziegler, Heinrich Ernst Author: Ziegler, Heinrich Ernst Recipient: Haeckel, Ernst Dating: 20.06.1889
POSTKARTE Ziegler, Heinrich Ernst Author: Ziegler, Heinrich Ernst Recipient: Haeckel, Ernst Dating: 14.01.1892
BRIEF [O.A.] Ziegler, Heinrich Ernst Author: Ziegler, Heinrich Ernst Recipient: Haeckel, Ernst Dating: 06.02.1895
BRIEF [O.A.] Ziegler, Heinrich Ernst Author: Ziegler, Heinrich Ernst Recipient: Haeckel, Ernst Dating: 04.02.1898