The Piano Sonata No. 11 in A major, K. 331 by Wolfgang Amadeus Mozart is a piano sonata in three movements. It is uncertain where and when Mozart composed the sonata; however, Vienna or Salzburg around 1783 is currently thought to be most likely (Paris and dates as far back as 1778 have also been suggested). Since the opening movement of this sonata is a theme and variation, Mozart defied the convention of beginning a sonata with an allegro movement in sonata form. The final in A minor is the famous Turkish March. – Ivo Pogorelich