BRIEF [O.A.] Hartmann, S... E... Author: Hartmann, S... E... Recipient: Haeckel, Ernst Dating: 16.01.1917
BRIEF [O.A.] Ortmann, Arnold E... Author: Ortmann, Arnold E... Recipient: Haeckel, Ernst Dating: 24.10.1894
BRIEF [O.A.] Hincke, Julius Author: Hincke, Julius Recipient: Haeckel, Ernst Corporation: "Iolink" Vineyards Dating: 22.03.1887
POSTKARTE Kertscher, Herbert R... Author: Kertscher, Herbert R... Recipient: Haeckel, Ernst Dating: 25.12.1913
BRIEF [O.A.] Kertscher, Herbert R... Author: Kertscher, Herbert R... Recipient: Haeckel, Ernst Corporation: Edda Verlag, Berlin Dating: 04.02.1914
BRIEF [O.A.] Kertscher, Herbert R... Author: Kertscher, Herbert R... Recipient: Haeckel, Ernst Corporation: Edda Verlag, Berlin Dating: 27.01.1915
