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b. 19

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

..

In the main text we add a cautionary  before d2.

category imprint: Editorial revisions

b. 28

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

d1 in chord in AI & GE

No d1 in AF (→FEEE)

..

The missing d1 minim in AF could be considered Chopin's hesitation: in AI it seems that the note was added to the g1-b1 third. It is also included in GE, based on [AG], which may be later. However, in analogous b. 120 a respective note is present in all sources, which may point towards the composer's oversight in the discussed place.

category imprint: Differences between sources; Corrections & alterations

issues: Chopin's hesitations , Errors of A

b. 33

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

..

In the main text we add cautionary naturals before b and a. The accidentals were also added in EE; the latter is also present in AI.

category imprint: Differences between sources; Editorial revisions

issues: EE revisions , Cautionary accidentals

b. 34

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

..

In AI and AF (→FE) there is no  restoring f at the end of the bar. The mistake was corrected in EE; the correct text is also featured in GE.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Omissions to cancel alteration , Errors of A

b. 37

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

..

The cautionary naturals before b1 and a1 were added while proofreading FE (→EE). The former is also in GE, perhaps also added at the proofreading stage. They are absent in the preserved autographs.

category imprint: Differences between sources

issues: GE revisions , Cautionary accidentals , FE revisions