Question: When did the former wife of Graf von Bismarck-Schönhausen donate a piece to the Smithsonian she purchased on her honeymoon with a different man?
Sentence (from "Kurt von Plettenberg"): Kurt Freiherr von Plettenberg (31 January 1891 in Bückeburg – 10 March 1945 in Berlin) was a German forester, cavalry officer and a member of the German Resistance (Widerstand).
Relevant evidence: No