BILDPOSTKARTE Haeckel, Ingeborg Author: Haeckel, Ingeborg Recipient: Haeckel, Ernst Dating: 1910.??.?? - 1916.??.??
BRIEF [O.A.] Schimmelmann, Frh. Hugo von Author: Schimmelmann, Frh. Hugo von Recipient: Haeckel, Ernst Dating: 29.12.1910
BRIEF [O.A.] Koppelow, Traugott von Author: Koppelow, Traugott von Recipient: Haeckel, Ernst Dating: 25.12.1910
BRIEF [O.A.] Meissner, E... F... A... Author: Meissner, E... F... A... Recipient: Haeckel, Ernst Dating: 16.12.1910
BRIEF [O.A.] Pettit, A... Author: Pettit, A... Recipient: Haeckel, Ernst Corporation: Société de Biologie Dating: 20.02.1910
BRIEF [O.A.] Ticehurst, J... N... G... Author: Ticehurst, J... N... G... Recipient: Haeckel, Ernst Dating: 17.10.1910