BRIEF [O.A.] Reh, Ludwig Author: Reh, Ludwig Recipient: Haeckel, Ernst Corporation: Naturhistorisches Museum Dating: 09.06.1894
BRIEF [O.A.] Reh, Ludwig Author: Reh, Ludwig Recipient: Haeckel, Ernst Corporation: Naturhistorisches Museum Dating: 09.07.1894
BRIEF [O.A.] Gaedechens, Rudolph Author: Gaedechens, Rudolph Recipient: Haeckel, Ernst Dating: 09.10.1894
POSTKARTE Recipient: Haeckel, Ernst Corporation: August Blumenthal, Transitus – Hamburg Dating: 09.12.1894