BRIEF [O.A.] Detadelur, C... F... Author: Detadelur, C... F... Recipient: Haeckel, Ernst Dating: 10.03.1907
BRIEF [O.A.] Furnemont, Leo Author: Furnemont, Leo Recipient: Haeckel, Ernst Corporation: Fédération Internationale de la Libre Pensée Dating: 18.06.1904
BRIEF [O.A.] Furnemont, Leo Author: Furnemont, Leo Recipient: Haeckel, Ernst Corporation: Fédération Internationale de la Libre Pensée Dating: 03.08.1904
BRIEF [O.A.] Furnemont, Leo Author: Furnemont, Leo Recipient: Haeckel, Ernst Corporation: Fédération Internationale de la Libre Pensée Dating: 24.06.1905
BRIEF [O.A.] Furnemont, Leo Author: Furnemont, Leo Recipient: Haeckel, Ernst Corporation: Fédération Internationale de la Libre Pensée Dating: 01.08.1905
BRIEF [O.A.] Furnemont, Leo Author: Furnemont, Leo Recipient: Haeckel, Ernst Corporation: Fédération Internationale de la Libre Pensée Dating: 16.10.1907
BRIEF [O.A.] Furnemont, Leo Author: Furnemont, Leo Recipient: Haeckel, Ernst Corporation: Fédération Internationale de la Libre Pensée Dating: 02.07.1910
PORTRÄTPOSTKARTE Friederici, Erna Author: Friederici, Erna Recipient: Haeckel, Ernst Dating: 24.08.1910