Busoni also made keyboard transcriptions of works by Mozart, Franz Schubert, Niels Gade and others in the period 1886–1891 for the publisher Breitkopf und Härtel. Later, during his earliest contacts with Arnold Schoenberg in 1909, he made a 'concert interpretation' of the latter's atonal Piano Piece, Op. 11, No. 2 (BV B 97) (which greatly annoyed Schoenberg himself). Busoni's own works sometimes feature incorporated elements of other composers' music. The fourth movement of "An die Jugend" (1909), for instance, uses two of Niccolò Paganini's Caprices for solo violin (numbers 11 and 15), while the 1920 piece "Piano Sonatina No. 6" ("Fantasia da camera super Carmen") is based on themes from Georges Bizet's opera "Carmen".