BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Haeckel, Carl & Charlotte [Eltern] Dating: 28.04.1871
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Haeckel, Carl & Charlotte [Eltern] Dating: 25.01.1871
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Haeckel, Carl & Charlotte [Eltern] Dating: 03.01.1871
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Haeckel, Carl & Charlotte [Eltern] Dating: 05.02.1871