BRIEF [O.A.] Fromentin, A... Author: Fromentin, A... Recipient: Haeckel, Ernst Corporation: Université Populaire de Mante Dating: 01.07.1903
BRIEF [O.A.] Gaul, Adolf Author: Gaul, Adolf Recipient: Haeckel, Ernst Corporation: Drogen-Handlung Dating: 19.06.1903
BRIEF [O.A.] Gaul, Adolf Author: Gaul, Adolf Recipient: Haeckel, Ernst Corporation: Drogen-Handlung Dating: 29.08.1903
BRIEF [O.A.] Foot, Clarina W... Author: Foot, Clarina W... Recipient: Haeckel, Ernst Dating: 08.11.1903