Issues : Last key signature sign

b. 6

composition: Op. 50 No. 3, Mazurka in C♯ minor

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Both autographs are lacking in the  raising a1 to a1. The mistake is also in EE, where it was repeated after the proof copy of FE. In the very FE Chopin added the overlooked accidental; the correct text is also in GE.

category imprint: Interpretations within context; Differences between sources

issues: Errors of A , Authentic corrections of FE , Last key signature sign , Errors repeated in EE

b. 45-57

composition: Op. 50 No. 3, Mazurka in C♯ minor

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On the basis of AI one can see that Chopin hesitated whether to write the B major section (from b. 45) using a 4- or a 5-sharp key signature. It is proven by the following actions: a new key signature was added in b. 45 and 57, then the sharps of A and a1 were removed in both places, while the sharps before the a notes in b. 50 and 52 (as well as in 61 and 74) were crossed out and then reintroduced. 

category imprint: Corrections & alterations; Source & stylistic information

issues: Chopin's hesitations , Last key signature sign , Corrections of AI

b. 168

composition: Op. 50 No. 3, Mazurka in C♯ minor

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In the main text we add a cautionary  before d. The accidental was also added in EE.
Following the example of GE, we omit the  before a1 at the end of the bar, which was unnecessarily repeated in the remaining sources.

category imprint: Differences between sources; Editorial revisions

issues: Cautionary accidentals , Last key signature sign