BRIEF [O.A.] Dodel, Frederick, Werner Author: Dodel, Frederick, Werner Recipient: Haeckel, Ernst Dating: 25.08.1906
BRIEF [O.A.] Dodel, Frederick Werner Author: Dodel, Frederick Werner Recipient: Haeckel, Ernst Dating: 17.12.1906
BRIEF [O.A.] Dodel, Frederick Werner Author: Dodel, Frederick Werner Recipient: Haeckel, Ernst Dating: 22.02.1907
BRIEF [O.A.] Dodel, Frederick Werner Author: Dodel, Frederick Werner Recipient: Haeckel, Ernst Dating: 15.04.1912
BRIEF [O.A.] Ringer, C... F... Author: Ringer, C... F... Recipient: Haeckel, Ernst Corporation: Bund der Freien Gemeinden und Freidenker-Vereine von Nord-Amerika Dating: 22.05.1911
BRIEF [O.A.] Bürger, Christina Author: Bürger, Christina Recipient: Haeckel, Ernst Dating: 17.08.1910
BRIEF [O.A.] Doerflinger, Carl Author: Doerflinger, Carl Recipient: Haeckel, Ernst Dating: 15.03.1877