Issues : Last key signature sign

b. 17

composition: Op. 24 No. 4, Mazurka in B♭ minor

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Before the quaver d flat2 in A (→GEFEEE) there is a . We remove that unnecessary sign in our main text. 

category imprint: Editorial revisions

issues: Cautionary accidentals , Last key signature sign

b. 17-18

composition: Op. 10 No 5, Etude in G♭ major

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The missing naturals raising c1 to c1 in A are a patent error by Chopin.

category imprint: Interpretations within context; Differences between sources

issues: Omission of current key accidentals , Errors of A , Authentic corrections of FE , Last key signature sign

b. 18

composition: Op. 26 No 2, Polonaise in E♭ minor

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The sources have cautionary flats next to c2 in the L.H. and c3 on 4th semiquaver in the R.H. Furthermore, in A – similarly to bar 17 –  next to c3 is repeated before the following crotchet.

category imprint: Differences between sources; Editorial revisions

issues: Cautionary accidentals , Last key signature sign

b. 18

composition: Op. 35, Sonata in B♭ minor, Mvt III

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In GC (→GE1) and FE there is no  raising g2 to g2. The frequently encountered in Chopin's works oversight was corrected in EE and GE2mar (→GE2). Similarly in bars 26, 72 and 80.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Errors in FE , Errors in GE , GE revisions , Omission of current key accidentals , Errors of A , Last key signature sign , Errors of GC

b. 18-20

composition: Op. 28 No. 13, Prelude in F♯ major

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The crossing-out visible in A before the 8th quaver in b. 18 covers probably a  (cautionary?) intended for e. Chopin realized that the accidental was not necessary here, yet in the next bars he would still write and cross out sharps before e notes, e.g. before E at the end of b. 20.

category imprint: Source & stylistic information

issues: Deletions in A , Last key signature sign