Issues : Authentic corrections of FE

b. 149-151

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

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In b. 149 and 151 the autographs are devoid of cautionary accidentals. In the first stage of proofreading of FE (→EE) a  was added before b in b. 151; the accidental is also present in GE. In the second stage of proofreading of FE before b was also added in b. 149; moreover, a  was repeated before the R.H. b note on the 3rd beat of the bar.
We include both naturals in the main text. 

category imprint: Differences between sources

issues: Cautionary accidentals , Authentic corrections of FE , FE revisions

b. 153

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

No marking in AI, AF & EE

in FE & GE

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The  indication was added in FE in the last stage of proofreading. Without [AG] it is difficult to say whether the same was true of GE or whether Chopin wrote it already in the aforementioned autograph.

category imprint: Differences between sources; Corrections & alterations

issues: Authentic corrections of FE

b. 168

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

No sign in AI, GE & EE

in AF

Long accent in FE

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Just like in analogous b. 160, in the main text we reproduce the mark of AF. The long accent in FE may result from Chopin's proofreading, which is indicated by the fact that EE does not contain any mark.

category imprint: Differences between sources; Corrections & alterations

issues: Long accents , Scope of dynamic hairpins , Authentic corrections of FE

b. 187

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

No indication in AI, AF, GE & EE

slentando in FE

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The indication slentando must be a Chopinesque addition introduced in the last stage of proofreading of FE.

category imprint: Differences between sources; Corrections & alterations

issues: Authentic corrections of FE