BRIEF [O.A.] Gierlichs, Florentine Author: Gierlichs, Florentine Recipient: Haeckel, Ernst Dating: 03.12.1863
BRIEF [O.A.] Gessenhardt, Johann Author: Gessenhardt, Johann Recipient: Haeckel, Ernst Dating: 21.05.1863
BRIEF [O.A.] Haeckel, Charlotte Author: Haeckel, Charlotte Recipient: Haeckel, Ernst Dating: 26.01.1863