BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Uslar-Gleichen, Bernhard von Dating: 12.05.1914
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Uslar-Gleichen, Bernhard von Dating: 11.12.1914
BRIEF [O.A.] Schmidt, Heinrich Author: Schmidt, Heinrich Recipient: Haeckel, Ernst Dating: 30.03.1914
BRIEF [O.A.] Trüper Author: Trüper Recipient: Haeckel, Ernst Corporation: Trüpers Erziehungsheim Sophienhöhe Dating: 20.10.1914
BRIEF [O.A.] Swing, Raymond E. Author: Swing, Raymond E. Recipient: Haeckel, Ernst Dating: 16.11.1914