The plenipotentiaries of the high powers who signed the treaty, The General Treaty of the Final Act of the Congress of Vienna… (1815)
“ ART. XVI. [26] The provinces and districts of the kingdom of Saxony, which are transferred to the dominion of his Majesty the King of Prussia, shall be distinguished by the name of the duchy of Saxony, and his Majesty shall add to his titles those of duke of Saxony, Landgrave of Thuringia, Margrave of the two Lusatias, and count of Henneberg. ”
