6 Preludes and Fugues, Op. 35 / 4. Prelude and Fugue in A-Flat Major, Op. 35, No. 4 : Mendelssohn: 6 Preludes and Fugues, Op. 35 / 4. Prelude and Fugue in A-Flat Major, Op. 35, No. 4: 1. Prelude, MWV U 122