BRIEF [O.A.] Sethe-Seyberth, Luise Author: Sethe-Seyberth, Luise Recipient: Haeckel, Ernst Dating: 25.05.1903
BRIEF [O.A.] Sethe-Seyberth, Luise Author: Sethe-Seyberth, Luise Recipient: Haeckel, Ernst Dating: 20.06.1903
BRIEF [O.A.] Sethe-Seyberth, Luise Author: Sethe-Seyberth, Luise Recipient: Haeckel, Ernst Dating: 06.10.1903