POSTKARTE Haeckel, Ernst Author: Haeckel, Ernst Recipient: Delle Grazie, Marie Eugenie Dating: 31.07.1897
POSTKARTE Haeckel, Ernst Author: Haeckel, Ernst Recipient: Delle Grazie, Marie Eugenie Dating: 29.10.1896
POSTKARTE Haeckel, Ernst Author: Haeckel, Ernst Recipient: N.N. Corporation: Zoologisches Institut der Universität Jena Dating: 10.10.1905
