Issues : Accidental below/above the note

b. 23

composition: Op. 10 No 6, Etude in E♭ minor

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In the chord in the middle of the bar, Chopin overlooked the  returning in A. However, two notes later he added a cautionary natural before (arranged a little bit too high).

category imprint: Interpretations within context; Differences between sources

issues: Omissions to cancel alteration , Errors of A , Authentic corrections of FE , Accidental below/above the note , Last key signature sign

b. 36

composition: Op. 10 No 6, Etude in E♭ minor

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In A the natural before the last semiquaver is written at least a third higher than the note.

category imprint: Source & stylistic information

issues: Accidental below/above the note