BRIEF [O.A.] Haeckel, Ernst Oskar Author: Haeckel, Ernst Oskar Recipient: Haeckel, Ernst Dating: 06.03.1907
BRIEF [O.A.] Schimmelmann, Frh. Hugo von Author: Schimmelmann, Frh. Hugo von Recipient: Haeckel, Ernst Dating: 14.02.1907
