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b. 63-64

composition: Op. 50 No. 2, Mazurka in A♭ major

Slur in A1 & GE

2 slurs in FE (→EE)

..

Two slurs in FE (→EE) may be explained by an unfinished (or simplified) correction, in which the top slur was added – perhaps by Chopin – as an amendment of the bottom one, moved by the engraver to the side of the noteheads (cf. b. 79-80, in which the same slur written above the stave in A1 was reproduced under the notes). In the main text we give the unequivocal notation of A1 and GE.

category imprint: Differences between sources

issues: Inaccuracies in FE , Placement of markings , Authentic corrections of FE , FE revisions

b. 65-66

composition: Op. 50 No. 2, Mazurka in A♭ major

No markings in A1 (→FEEE)

cresc. in GE

..

In the main text we give the cresc. indication in b. 65 and the  mark in b. 66, added by Chopin probably in the proofreading of GE1. The composer replaced with them the accents on the 3rd beat of those bars, present in A1 (→FEEE). The change shows a version of dynamics with longer breath, closer related to the ascending melodic sequence, as superior to a regular mazurka accentation.

category imprint: Differences between sources; Corrections & alterations

issues: Authentic corrections of GE

b. 65-66

composition: Op. 50 No. 2, Mazurka in A♭ major

Short & long accent in A1, literal reading

2 short accents in FE (→EE)

No accents in GE

..

The accents on the 3rd beat of these bars were probably removed in the proofreading of GE and replaced by Chopin with the cresc. and  markings (it is indicated by the traces of removal of analogous marks in b. 81-82). Therefore, we do not include them in the main text.
The issue concerning the length of the accents: see b. 60-64.

category imprint: Graphic ambiguousness; Differences between sources; Corrections & alterations

issues: Long accents , Authentic corrections of GE , Inaccuracies in A

b. 65-66

composition: Op. 50 No. 2, Mazurka in A♭ major

c1 repeated in A1 & GE

c1 tied in FE (→EE)

..

The tie of c1 is probably a slur of A1, distorted due to a routine shift to the side of noteheads. It is indicated by b. 77-78, in which the slur of A1, written in the same manner, was reproduced in FE as a tie of c1. The right slur, yet also inaccurately reproduced, was probably added in the proofreading of FE (→EE), perhaps by Chopin. We consider the misleading tie of c1 having been left in the text to be an inaccuracy committed in the implementation of the proofreading. In the main text we give the unambiguous notation of A1 and GE

category imprint: Interpretations within context; Differences between sources

issues: Inaccuracies in FE , Placement of markings , Authentic corrections of FE

b. 65

composition: Op. 50 No. 2, Mazurka in A♭ major

"Vertical" slur in A1 & GE1

Conventional slur in FE & GE2

No slur in EE

..

In the main text we give the concordant notation of A1 and GE, the only authentic one. The remaining versions are inaccuracies or revisions.

category imprint: Differences between sources

issues: Inaccuracies in FE , Errors in EE , GE revisions