POSTKARTE Grazie, Marie Eugenie delle Author: Grazie, Marie Eugenie delle Recipient: Haeckel, Ernst Dating: 22.08.1903
BRIEF OHNE UMSCHLAG Ehrenberg, Paul Author: Ehrenberg, Paul Recipient: Haeckel, Ernst Dating: 31.12.1903
BRIEF [O.A.] Frapau-Akunian, Ilse Author: Frapau-Akunian, Ilse Recipient: Haeckel, Ernst Dating: 16.05.1903
BRIEF [O.A.] Eggeling, Heinrich von Author: Eggeling, Heinrich von Recipient: Haeckel, Ernst Dating: 31.12.1903
BRIEF [O.A.] Fenizia, Carlo Author: Fenizia, Carlo Recipient: Haeckel, Ernst Corporation: Société pour la Diffusion des Sciences Physiques et Naturelles et de Leurs Applications Dating: 05.05.1903
POSTKARTE Finsterbusch, Helene Author: Finsterbusch, Helene Recipient: Haeckel, Ernst Dating: 07.08.1903
BRIEF OHNE UMSCHLAG Ellram, Arthur Author: Ellram, Arthur Recipient: Haeckel, Ernst Dating: 12.02.1903
