Simplify the following text for a Grade 11 native English-speaking person.
Original: As well as composing prolifically , DuprÃ prepared study editions of the organ works of Bach , Handel , Mozart , Liszt , Mendelssohn , Schumann , CÃ sar Franck , and Alexander Glazunov .
Simplified: As well as composing lots of music , DuprÃ prepared study editions of the organ works of Bach , Handel , Mozart , Liszt , Mendelssohn , Schumann , CÃ sar Franck , and Alexander Glazunov .