POSTKARTE Perscheid, V... Nicola Author: Perscheid, V... Nicola Recipient: Haeckel, Ernst Dating: 20.04.1904
BRIEF [O.A.] Perscheid, V... Nicola Author: Perscheid, V... Nicola Recipient: Haeckel, Ernst Dating: 20.06.1904
BRIEF [O.A.] Perscheid, V... Nicola Author: Perscheid, V... Nicola Recipient: Haeckel, Ernst Dating: 10.07.1904
BRIEF [O.A.] Perscheid, V... Nicola Author: Perscheid, V... Nicola Recipient: Haeckel, Ernst Dating: 18.07.1904