BRIEF [O.A.] Rottenburg, Paul von Author: Rottenburg, Paul von Recipient: Haeckel, Ernst Dating: 21.10.1886
BRIEF [O.A.] Rottenburg, Paul von Author: Rottenburg, Paul von Recipient: Haeckel, Ernst Dating: 03.01.1886
BRIEF [O.A.] Rottenburg, Paul von Author: Rottenburg, Paul von Recipient: Haeckel, Ernst Dating: 30.05.1886
BRIEF [O.A.] Rottenburg, Paul von Author: Rottenburg, Paul von Recipient: Haeckel, Ernst Dating: 07.10.1886
BRIEF [O.A.] Hanitsch, Richard Author: Hanitsch, Richard Recipient: Haeckel, Ernst Dating: 04.08.1886