BRIEF OHNE UMSCHLAG Wetzler, Hans; Haar, Robert Author: Wetzler, Hans; Haar, Robert Recipient: Haeckel, Ernst Dating: 16.02.1912
BRIEF OHNE UMSCHLAG Recipient: Haeckel, Ernst Corporation: Wiener Bank-Verein. Filiale Prag. Dating: 15.02.1912
BRIEF OHNE UMSCHLAG Umrath, Wilhelm Author: Umrath, Wilhelm Recipient: Haeckel, Ernst Dating: 15.02.1912