BRIEF [O.A.] Geinitz, Hans Bruno Author: Geinitz, Hans Bruno Recipient: Haeckel, Ernst Dating: 19.02.1885
BRIEF [O.A.] Freytag, G... Author: Freytag, G... Recipient: Haeckel, Ernst Corporation: Verlagsbuchhandlung, F. Tempsky und G. Freytag Dating: 18.04.1885
BRIEF [O.A.] Freytag, G... Author: Freytag, G... Recipient: Haeckel, Ernst Corporation: Verlagsbuchhandlung, F. Tempsky und G. Freytag Dating: 28.05.1885
BRIEF [O.A.] Eberlein, Richard Author: Eberlein, Richard Recipient: Haeckel, Ernst Corporation: Richard Eberlein Bank-Geschäft Dating: 01.07.1885