BILDPOSTKARTE Becker, Franz Johann Jakob Emil Author: Becker, Franz Johann Jakob Emil Recipient: Haeckel, Ernst Dating: 20.08.1917
BILDPOSTKARTE Grimsehl, Carl; Grimsehl, M. Author: Grimsehl, Carl; Grimsehl, M. Recipient: Haeckel, Ernst Dating: 22.09.1917
BILDPOSTKARTE Crompton, Ella von Author: Crompton, Ella von Recipient: Haeckel, Ernst Dating: 29.12.1917
BILDPOSTKARTE Crompton, Ella von Author: Crompton, Ella von Recipient: Haeckel, Ernst Dating: 15.08.1917