BRIEF [O.A.] Beneke-Schröer, A... Author: Beneke-Schröer, A... Recipient: Haeckel, Ernst Dating: 12.12.1909
BRIEF [O.A.] Bessey, Charles E... Author: Bessey, Charles E... Recipient: Haeckel, Ernst Corporation: The University of Nebraska, Department of Botany Dating: 08.05.1909
BRIEF OHNE UMSCHLAG Bedriaga, Jacques von Author: Bedriaga, Jacques von Recipient: Haeckel, Ernst Dating: 14.02.1909
BRIEF OHNE UMSCHLAG Becker, Franz Johann Jakob Emil Author: Becker, Franz Johann Jakob Emil Recipient: Haeckel, Ernst Dating: 27.01.1909
BRIEF OHNE UMSCHLAG Becker, Franz Johann Jakob Emil Author: Becker, Franz Johann Jakob Emil Recipient: Haeckel, Ernst Dating: ??.12.1909
BRIEF [O.A.] Behm, Hans Wolfgang Author: Behm, Hans Wolfgang Recipient: Haeckel, Ernst Dating: 11.04.1909
BRIEF [O.A.] Behm, Hans Wolfgang Author: Behm, Hans Wolfgang Recipient: Haeckel, Ernst Dating: 14.04.1909
BRIEF [O.A.] Behm, Hans Wolfgang Author: Behm, Hans Wolfgang Recipient: Haeckel, Ernst Dating: 04.11.1909