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b. 17

composition: Op. 28 No. 21, Prelude in B♭ major

Staccato dot in A

No mark in remaining sources

..

As was the case in b. 13, in the main text we include the staccato dot written in A and omitted in all the remaining sources.

category imprint: Differences between sources

issues: Errors in FE , Errors of FC

b. 17

composition: Op. 28 No. 21, Prelude in B♭ major

No fingering in A (→FE,FCGE)

Fingering in EE

category imprint: Differences between sources

issues: EE revisions

b. 18-20

composition: Op. 28 No. 21, Prelude in B♭ major

..

In A (→FE) there is not a single  lowering d to d in these bars. Chopin's patent inaccuracy was corrected in FC (→GE) and EE.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Accidentals in different octaves , Fontana's revisions , Inaccuracies in A , Errors repeated in FE

b. 19-23

composition: Op. 28 No. 21, Prelude in B♭ major

..

In A Chopin overlooked a few necessary flats in the R.H. part: in b. 19 d2, in b. 21 d3 and g2, in b. 22 d2 and d3. FC added only the first  in b. 21; in addition, the copyist overlooked the  of g2 in b. 23. FE also added only some of the necessary flats, next to d2(3) in b. 21-22, and – which is puzzling – also overlooked the  of g2 in b. 23. GE and EE added all necessary accidentals.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Errors in FE , Accidentals in different octaves , GE revisions , Omission of current key accidentals , FE revisions , Inaccuracies in FC , Fontana's revisions , Inaccuracies in A , Errors repeated in FE

b. 21-22

composition: Op. 28 No. 21, Prelude in B♭ major

..

In these bars Chopin did not enter any accidentals into the L.H. part at all. All necessary flats were added in FC (→GE); they are also in EE. In turn, FE added accidentals only before the fifths that open the bars.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Omission of current key accidentals , Errors of A , FE revisions , Fontana's revisions , Errors repeated in FE