BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Ehrlich, Franz Carl Dating: 01.07.1856
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Hellwald, Friedrich von Dating: 24.02.1874
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Hellwald, Friedrich von Dating: 23.06.1874
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Hellwald, Friedrich von Dating: 22.10.1874
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Hellwald, Friedrich von Dating: 22.11.1874
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Hellwald, Friedrich von Dating: 01.12.1874
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Hellwald, Friedrich von Dating: 18.12.1876
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Hellwald, Friedrich von Dating: 22.12.1884
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Hellwald, Friedrich von Dating: 07.02.1875
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Hellwald, Friedrich von Dating: 13.02.1875