BRIEF OHNE UMSCHLAG Finsterbusch, Ludwig Author: Finsterbusch, Ludwig Recipient: Haeckel, Ernst Dating: 17.07.1867
POSTKARTE Finsterbusch, Ludwig Author: Finsterbusch, Ludwig Recipient: Haeckel, Ernst Dating: 17.08.1885
BRIEF OHNE UMSCHLAG Heinemann, August Author: Heinemann, August Recipient: Haeckel, Ernst Dating: 24.06.1842
BRIEF OHNE UMSCHLAG Heinemann, August Author: Heinemann, August Recipient: Haeckel, Ernst Dating: 23.07.1842
BRIEF OHNE UMSCHLAG Osterwald, Wilhelm Author: Osterwald, Wilhelm Recipient: Haeckel, Ernst Dating: 04.04.1852
BRIEF OHNE UMSCHLAG Osterwald, Wilhelm Author: Osterwald, Wilhelm Recipient: Haeckel, Ernst Dating: 03.05.1852