BRIEF [O.A.] Cox, Katherine H... Author: Cox, Katherine H... Recipient: Haeckel, Ernst Dating: 13.01.1908
BRIEF [O.A.] Cobb, Nathan Augustus Author: Cobb, Nathan Augustus Recipient: Haeckel, Ernst Dating: 11.12.1889
BRIEF OHNE UMSCHLAG Ankenbrand, Ludwig Author: Ankenbrand, Ludwig Recipient: Haeckel, Ernst Dating: 04.02.1916
BRIEF OHNE UMSCHLAG Ankenbrand, Ludwig Author: Ankenbrand, Ludwig Recipient: Haeckel, Ernst Corporation: Concentration Camps Dating: 16.02.1917
BRIEF MIT UMSCHLAG Ankenbrand, Ludwig Author: Ankenbrand, Ludwig Recipient: Haeckel, Ernst Corporation: Service des Prisonniers de Guerre Dating: 10.01.1919
BRIEF MIT UMSCHLAG Ankenbrand, Ludwig Author: Ankenbrand, Ludwig Recipient: Haeckel, Ernst Corporation: Service des Prisonniers de Guerre Dating: 15.01.1919
BRIEF OHNE UMSCHLAG Behrendt, Peter Author: Behrendt, Peter Recipient: Haeckel, Ernst Corporation: Palmer, Scott & Co. Dating: 12.12.1882
BRIEF [O.A.] Recipient: Haeckel, Walter Corporation: The Rationalist Press Association Dating: 10.09.1919
BRIEF [O.A.] Weidenbach, Max F... Author: Weidenbach, Max F... Recipient: Haeckel, Ernst Dating: 19.04.1877