Symphony No. 11 in D major, K. 84/73q, was at one time considered unquestionably to be the work of Wolfgang Amadeus Mozart. Its status has, however, been challenged, and remains uncertain. It is believed to date from 1770, and may have been written in Milan or Bologna, if it is a genuine Mozart work. An early manuscript from Vienna attributes the work to Wolfgang, but nineteenth-century copies of the score attribute it respectively to Leopold Mozart and to Carl Dittersdorf. Neal Zaslaw writes: "A comparison of the results of two stylistic analyses of the work's first movement with analyses of unquestionably genuine first movements of the period by the three composers suggests that Wolfgang is the most likely of the three to have been the composer of K73q".
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