BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Engelmann, Wilhelm Dating: 20.02.1906
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Engelmann, Wilhelm Dating: 17.07.1917
BRIEFABSCHRIFT Haeckel, Ernst Author: Haeckel, Ernst Recipient: Engelmann, Wilhelm Dating: 30.06.1864
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Engelmann, Wilhelm Corporation: Zoologisches Institut der Universität Jena Dating: 30.03.1888
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Engelmann, Wilhelm Corporation: Zoologisches Institut Dating: 02.07.1888
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Engelmann, Wilhelm Dating: 15.07.1888
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Engelmann, Wilhelm Dating: 27.07.1888
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Engelmann, Wilhelm Dating: 18.08.1888
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Engelmann, Wilhelm Dating: 20.12.1888
