BILDPOSTKARTE Haeckel, Ingeborg Author: Haeckel, Ingeborg Recipient: Haeckel, Ernst Dating: 1910.??.?? - 1916.??.??
BILDPOSTKARTE Meyer, Elisabeth Author: Meyer, Elisabeth Recipient: Haeckel, Ernst; Haeckel, Agnes [Eltern] Dating: 1909.??.?? [Weihnachten]
BILDPOSTKARTE Dreyspring, Carl; Dreyspring, [Frau] Author: Dreyspring, Carl; Dreyspring, [Frau] Recipient: Haeckel, Ernst Dating: 16.02.1909
BILDPOSTKARTE Max, Ernestine von, geb. Harlander Author: Max, Ernestine von, geb. Harlander Recipient: Haeckel, Ernst Dating: 16.02.1909
BILDPOSTKARTE Ziegler, Heinrich Ernst; Ziegler, Frieda, geb. Busch Author: Ziegler, Heinrich Ernst; Ziegler, Frieda, geb. Busch Recipient: Haeckel, Ernst Dating: 28.12.1899