BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Krauseneck, Heinrich Dating: 14.02.1889
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Krauseneck, Heinrich Dating: 14.05.1889
BRIEF [O.A.] Haeckel, Ernst Author: Haeckel, Ernst Recipient: Krauseneck, Heinrich Dating: 28.12.1889
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Rottenburg, Paul von Dating: 21.02.1889
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Rottenburg, Paul von Dating: 03.05.1889
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Rottenburg, Paul von Dating: 24.08.1889
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Rottenburg, Paul von Dating: 28.08.1889
BRIEF OHNE UMSCHLAG Haeckel, Ernst Author: Haeckel, Ernst Recipient: Rottenburg, Paul von Dating: 30.08.1889