BRIEF [O.A.] Arbesser, Cäsar v. Author: Arbesser, Cäsar v. Recipient: Haeckel, Ernst Dating: 08.04.1911
BRIEF [O.A.] Arbesser, Cäsar v. Author: Arbesser, Cäsar v. Recipient: Haeckel, Ernst Dating: 16.04.1911
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Unbekannt (Mutter?) Dating: 14.04.1878
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Familie Haeckel in Jena und Potsdam Dating: 20.04.1878
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Familie Haeckel in Potsdam Dating: 21.04.1878
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Familie Haeckel in Potsdam Dating: 26.04.1878
BRIEF OHNE UMSCHLAG Marojevic, Bonagracija Author: Marojevic, Bonagracija Recipient: Haeckel, Ernst Dating: 07.07.1871
BRIEF OHNE UMSCHLAG Marojevic, Bonagracija Author: Marojevic, Bonagracija Recipient: Haeckel, Ernst Dating: 18.11.1871
BRIEF OHNE UMSCHLAG Marojevic, Bonagracija Author: Marojevic, Bonagracija Recipient: Haeckel, Ernst Dating: 26.07.1872
BRIEF OHNE UMSCHLAG Marojevic, Bonagracija Author: Marojevic, Bonagracija Recipient: Haeckel, Ernst Dating: 03.11.1874