BRIEF [O.A.] Focke, Gustav Waldemar Author: Focke, Gustav Waldemar Recipient: Haeckel, Ernst Dating: 16.07.1866
BRIEF [O.A.] Focke, Gustav Waldemar Author: Focke, Gustav Waldemar Recipient: Haeckel, Ernst Dating: 11.08.1866
BRIEF [O.A.] Endemann, Wilhelm Author: Endemann, Wilhelm Recipient: Haeckel, Charlotte Dating: 22.10.1866
BRIEF [O.A.] Endemann, Wilhelm Author: Endemann, Wilhelm Recipient: Haeckel, Charlotte Dating: 23.11.1866
BRIEF [O.A.] Gildemeister, E... Author: Gildemeister, E... Recipient: Haeckel, Ernst Dating: 02.04.1866
BRIEF [O.A.] Kauffmann, Julius Author: Kauffmann, Julius Recipient: Haeckel, Ernst Dating: 18.09.1866
BRIEF OHNE UMSCHLAG Keferstein, Wilhelm Author: Keferstein, Wilhelm Recipient: Haeckel, Ernst Dating: 17.01.1866
