BRIEF OHNE UMSCHLAG Almeroth, Hans Author: Almeroth, Hans Recipient: Haeckel, Ernst Dating: 21.07.1913
BRIEF [O.A.] Bardeleben, Karl von Author: Bardeleben, Karl von Recipient: Haeckel, Ernst Corporation: Anatomische Gesellschaft Dating: 17.03.1913
BRIEF [O.A.] Avenarius, Hannes Author: Avenarius, Hannes Recipient: Haeckel, Ernst Dating: 13.10.1913
BRIEF OHNE UMSCHLAG Almeroth, Hans Author: Almeroth, Hans Recipient: Haeckel, Ernst Dating: 17.07.1913
BRIEF [O.A.] Recipient: Haeckel, Ernst Corporation: Apollowerk G.m.b.H., Kunstanstalt und Verlag Dating: 03.06.1913
BRIEF [O.A.] Recipient: Haeckel, Ernst Corporation: Apollowerk G.m.b.H., Kunstanstalt und Verlag Dating: 28.07.1913