24 preludes in quarter-tone system (1934/70) (excerpts): xxiv.
24 preludes in quarter-tone system (1934/70) (excerpts): viii.
24 preludes in quarter-tone system (1934/70) (excerpts): xxi.
24 preludes in quarter-tone system (1934/70) (excerpts): xiv.
24 preludes in quarter-tone system (1934/70) (excerpts): xxiii.
24 preludes in quarter-tone system (1934/70) (excerpts): xvii.
24 preludes in quarter-tone system (1934/70) (excerpts): xviii.