BRIEF OHNE UMSCHLAG Allmers, Hermann Author: Allmers, Hermann Recipient: Haeckel, Ernst Dating: 22.02.1897
BRIEF OHNE UMSCHLAG Allmers, Hermann Author: Allmers, Hermann Recipient: Haeckel, Ernst Dating: 29.04.1897
BRIEF OHNE UMSCHLAG Allmers, Hermann Author: Allmers, Hermann Recipient: Haeckel, Ernst Dating: 30.10.1897