BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 02.09.1896
BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 09.11.1896
BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 27.01.1897
BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 21.02.1899
BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 24.04.1900
BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 30.03.1900
BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 12.04.1900
BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 25.06.1900
BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 04.07.1900
BRIEF [O.A.] Schleicher, Fréres Author: Schleicher, Fréres Recipient: Haeckel, Ernst Dating: 11.06.1902