BRIEF OHNE UMSCHLAG Westien, Heinrich Author: Westien, Heinrich Recipient: Haeckel, Ernst Dating: 12.08.1893
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