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
BRIEF OHNE UMSCHLAG Bernard, Matilda Author: Bernard, Matilda Recipient: Haeckel, Ernst Dating: 12.11.1893
BRIEF OHNE UMSCHLAG Besser, Leopold Author: Besser, Leopold Recipient: Haeckel, Ernst Dating: 05.07.1893
BRIEF OHNE UMSCHLAG Besser, Leopold Author: Besser, Leopold Recipient: Haeckel, Ernst Dating: 12.07.1893