BRIEF OHNE UMSCHLAG Carneri, Bartholomäus von Author: Carneri, Bartholomäus von Recipient: Haeckel, Ernst Dating: 22.05.1888
BRIEF [O.A.] Schweiger-Lerchenfeld [Baron] Author: Schweiger-Lerchenfeld [Baron] Recipient: Haeckel, Ernst Dating: 04.02.1888