BRIEF OHNE UMSCHLAG Singer, Isidore Author: Singer, Isidore Recipient: Haeckel, Ernst Dating: 14.08.1884
BRIEF OHNE UMSCHLAG Singer, Isidore Author: Singer, Isidore Recipient: Haeckel, Ernst Dating: 12.07.1884
BRIEF OHNE UMSCHLAG Singer, Isidore Author: Singer, Isidore Recipient: Haeckel, Ernst Dating: 17.11.1884
BRIEF [O.A.] Shompzon, Daray W... Author: Shompzon, Daray W... Recipient: Haeckel, Ernst Dating: 04.02.1884
BRIEF OHNE UMSCHLAG Geddes, Patrick Author: Geddes, Patrick Recipient: Haeckel, Ernst Dating: ??.??.1884
BRIEF [O.A.] Settegast, Henry Author: Settegast, Henry Recipient: Haeckel, Ernst Corporation: Königl. landw. Hochschule Dating: 04.02.1884