Mozart's name by Mozart scholar Michael Lorenz in the registers of the Lower Austrian Governorship, where in May 1787 "Mozart Wolfgang Amadeus" is referred to as having applied for the return of his written surety for his friend . Other uses of "Amadeus", from immediately after Mozart's death in 1791, are given above. The 19th century saw the gradual victory of "Amadeus" over alternative middle names. The earliest (18th century) biographers of Mozart, such as Friedrich Schlichtegroll and Franz Niemetschek, used "Gottlieb". However, in 1798 the publishing firm of Breitkopf & Härtel began to issue a (partial) Complete Works edition under the
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