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b. 7

composition: Op. 30 No. 1, Mazurka in C minor

e1 in FE (→EE)

No note in FC (→GE)

..

The missing e1 crotchet at the beginning of the bar must be an oversight by Fontana.

category imprint: Differences between sources

issues: Errors of FC

b. 8-16

composition: Op. 30 No. 1, Mazurka in C minor

No marks in FE (→EE)

Long accents in FC

Short accents in GE

..

The accent in bar 8 entered into FC is undoubtedly a long accent. Therefore, it allows us to consider the less unambiguous accent placed in a similar context in bar 16 to be long too. Both marks were almost certainly added by Chopin. In GE all accents in this Mazurka are more or less of the same length, and we reproduce them as short. 

category imprint: Graphic ambiguousness; Differences between sources

issues: Long accents , Authentic corrections of FC

b. 9

composition: Op. 30 No. 1, Mazurka in C minor

No accidental in FC & FE (→EE)

 to c2 in GE

..

The cautionary  added in pencil to FC comes from the reviser of GE1, hence we do not include it in the text of the copy. The mark was taken into account only by GE.
The same in bar 45.

category imprint: Differences between sources; Source & stylistic information

issues: GE revisions , Foreign hand additions in manuscripts

b. 17-19

composition: Op. 30 No. 1, Mazurka in C minor

No marks in FE (→EE)

Long accents in FC

Short accents in GE

..

Chopin added the long accents in bars 17 and 19 in FC. In GE they were reproduced as medium marks, which we interpret as short – see bar 1.

category imprint: Differences between sources

issues: Long accents , Authentic corrections of FC

b. 24

composition: Op. 30 No. 1, Mazurka in C minor

..

The sources do not include a  restoring b on the 3rd beat of the bar, which means that this accidental was also absent in [A]. In the main text, we correct this oversight, patent in this harmonic context and generally fairly typical of Chopin.

category imprint: Editorial revisions

issues: Omissions to cancel alteration , Errors of A , Errors of FC , Errors repeated in GE , Errors repeated in FE , Errors repeated in EE