TELEGRAMM Haeckel, Ernst Author: Haeckel, Ernst Recipient: Haeckel, Charlotte [Mutter] Dating: 29.09.1868
TELEGRAMM Haeckel, Ernst Author: Haeckel, Ernst Recipient: Haeckel, Charlotte [Mutter] Dating: 12.09.1869
TELEGRAMM Haeckel, Ernst Author: Haeckel, Ernst Recipient: Haeckel, Charlotte [Mutter] Dating: 30.09.1871