Issues : Last key signature sign

b. 23

composition: Op. 25 No 8, Etude in D♭ major

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All sources include a  before g2. The sign does not seem to be necessary here, as it already appears in the previous bar.

category imprint: Editorial revisions

issues: Cautionary accidentals , Last key signature sign

b. 32-34

composition: Op. 25 No 8, Etude in D♭ major

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The notation of the three-bar chromatic progression does not contain errors in the sources, yet some of the cautionary signs seem to be unnecessary. In the main text we leave only the naturals before and in the last triplet of each bar, as these are notes before which one can expect signs in the D major key (in A and FE Chopin omitted only the last of them, before e3 in bar 34, completed in GE1). In A (→GE1) and FE Chopin also added flats before a2 and b2 in bar 33 and a3 and b3 in bar 34. In EE, particularly in GE2 (→GE3), a few bars were added in each bar.
In Chopin notation it is the orthography of the 6th sixth in each of these bars that draws attention – Chopin consistently writes a-f instead of b-g, which are proper of the D major key. 

category imprint: Differences between sources; Editorial revisions

issues: EE revisions , GE revisions , Cautionary accidentals , Last key signature sign