POSTKARTE Blochmann, Friedrich Author: Blochmann, Friedrich Recipient: Haeckel, Ernst Dating: 01.01.1893
POSTKARTE Blochmann, Friedrich Author: Blochmann, Friedrich Recipient: Haeckel, Ernst Dating: 05.11.1893
POSTKARTE Böhm, Carl Author: Böhm, Carl Recipient: Haeckel, Ernst Corporation: Carl Böhm's Hotel am See Dating: 11.08.1893
POSTKARTE Dahl, Friedrich Author: Dahl, Friedrich Recipient: Haeckel, Ernst Corporation: Zoolog. Institut Dating: 30.01.1893
POSTKARTE Erdmann, Gustav Adolf Author: Erdmann, Gustav Adolf Recipient: Haeckel, Ernst Dating: 24.04.1893