Wolfgang Amadeus Mozart rapidly maturing composer. Wolfgang met Josef Mysliveček and Giovanni Battista Martini in Bologna, and was accepted as a member of the famous Accademia Filarmonica. In Rome, he heard Gregorio Allegri's "Miserere" twice in performance, in the Sistine Chapel, and wrote it out from memory, thus producing the first unauthorized copy of this closely guarded property of the Vatican. In Milan, Mozart wrote the opera "Mitridate, re di Ponto" (1770), which was performed with success. This led to further opera commissions. He returned with his father twice to Milan (August–December 1771; October 1772 – March 1773) for the composition and premieres
Wolfgang Amadeus Mozart performed Mozart's operas while playing in the court orchestra at Bonn, and traveled to Vienna in 1787 hoping to study with the older composer. Some of have direct models in comparable works by Mozart, and he wrote cadenzas (WoO 58) to Mozart's D minor piano concerto K. 466. For further details see Mozart and Beethoven. Composers have paid homage to Mozart by writing sets of variations on his themes. Beethoven wrote four such sets (Op. 66, WoO 28, WoO 40, WoO 46). Others include Fernando Sor's Introduction and Variations on a Theme by Mozart (1821), Mikhail Glinka's Variations on a