BRIEF MIT UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Delle Grazie, Marie Eugenie Dating: 27.09.1896
ANSICHTSKARTE Kölliker, Albert von Author: Kölliker, Albert von Recipient: Haeckel, Ernst Dating: ??.??.1896
BRIEF [O.A.] Dammer, Otto Author: Dammer, Otto Recipient: Haeckel, Ernst Corporation: Meyers Konversations-Lexikon, Redaktion Dating: 23.08.1896
BRIEF [O.A.] Dammer, Otto Author: Dammer, Otto Recipient: Haeckel, Ernst Corporation: Meyers Konversations-Lexikon, Redaktion Dating: 01.10.1896
BRIEF [O.A.] Dammer, Otto Author: Dammer, Otto Recipient: Haeckel, Ernst Corporation: Meyers Konversations-Lexikon, Redaktion Dating: 29.11.1896