BRIEF [O.A.] Domenichini, Mario Author: Domenichini, Mario Recipient: Haeckel, Ernst Dating: 20.02.1907
BRIEF [O.A.] Domenichini, Mario Author: Domenichini, Mario Recipient: Haeckel, Ernst Dating: 27.02.1907
BRIEF [O.A.] Domenichini, Mario Author: Domenichini, Mario Recipient: Haeckel, Ernst Dating: 31.05.1907
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Krauseneck, Heinrich Dating: 30.03.1878
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Krauseneck, Heinrich Dating: 03.04.1878
BRIEF [O.A.] Pelet-Narbonne, Stephanie von Author: Pelet-Narbonne, Stephanie von Recipient: Haeckel, Ernst Dating: 29.02.1896