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b. 66

composition: Op. 30 No. 4, Mazurka in C# minor

..

We add a cautionary  before b1 in the main text.

category imprint: Editorial revisions

b. 67-68

composition: Op. 30 No. 4, Mazurka in C# minor

No sign in FC (→GE)

in FE (→EE)

..

The  hairpin could have been added by Chopin while proofreading FE or overlooked by the copyist in FC.

category imprint: Differences between sources

issues: Authentic corrections of FE , Errors of FC

b. 67

composition: Op. 30 No. 4, Mazurka in C# minor

..

The cautionary natural before e1 is to be found only in FC (→GE).

category imprint: Differences between sources

issues: Cautionary accidentals

b. 69-73

composition: Op. 30 No. 4, Mazurka in C# minor

..

The dynamic indications, cresc. - - - , were added to FC by Chopin, hence they were probably also added in the stage of proofreading FE or to the basis thereof.

category imprint: Corrections & alterations; Source & stylistic information

issues: Authentic corrections of FE , Authentic corrections of FC

b. 69

composition: Op. 30 No. 4, Mazurka in C# minor

..

In FE there is no  raising a to a. The patent inadvertence, typical of Chopin, was corrected in EE. The correct text is also to be found in FC (→GE).

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Accidentals in different octaves , Inaccuracies in FE