"Diplomatenduett" from the operetta "Die lustige Witwe" ("The Merry Widow") (Revision 1939) "Diplomatenduett" from the operetta "Die lustige Witwe" ("The Merry Widow") (Revision 1939) Libretto Victor Léon Libretto Leo Stein Main opus "Die lustige Witwe" ("The Merry Widow"), Operetta in three acts