Impromptu No. 4 In C Sharp Minor, Op. 66 "Fantaisie-Impromptu" - Chopin: Impromptu No. 4 In C Sharp Minor, Op. 66 "Fantaisie-Impromptu": Allegro agitato (Impromptu No.4 In C Sharp Minor, Op.66 "Fantaisie-Impromptu": ゲンソウソッキョウキョク|Impromptu No.4 In C Sharp Minor, Op.66 "Fantaisie-Impromptu": 幻想即興曲 作品66)