BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Uslar-Gleichen, Bernhard von Dating: 11.06.1911
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Uslar-Gleichen, Bernhard von Dating: 06.09.1911
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Uslar-Gleichen, Bernhard von Dating: 11.12.1911
BRIEF [O.A.] Grimaldi, Vincento Author: Grimaldi, Vincento Recipient: Haeckel, Ernst Corporation: Associazione di Publica Assistenza Dating: 13.04.1911
BRIEF [O.A.] Greil, Alfred Author: Greil, Alfred Recipient: Haeckel, Ernst Corporation: K. K. Anatomisches Institut zu Innsbruck Dating: 22.12.1911
BRIEF [O.A.] Dresser, C... H... Author: Dresser, C... H... Recipient: Haeckel, Ernst Corporation: C. H. Dresser & Son Inc. Dating: 20.05.1911