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b. 6

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

..

The crossing-out in A reveals the initial version of the beginning of this bar: .

category imprint: Corrections & alterations; Source & stylistic information

issues: Corrections in A , Deletions in A , Main-line changes

b. 6-7

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

..

In A the end of the L.H. slur in b. 6, which closes the line, clearly points to continuation, which is, however, absent in b. 7. In this case, it did not result in discrepancies in the remaining sources, since both FE (→EE) and FC (→GE) led the slur to the beginning of b. 7, undoubtedly in accordance with Chopin's intention.

category imprint: Graphic ambiguousness; Source & stylistic information

issues: Inaccurate slurs in A , Uncertain slur continuation

b. 6

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

..

In A (→FE,FCGE) there is a  before the d2 crotchet. In the main text we omit the accidental, which was also performed in EE. The use of g1 and g in the L.H. part in the previous bar and on the 2nd quaver in this bar provides the fragment preceding the discussed note with a minor tone, which probably resulted in the need to specify its pitch.

category imprint: Differences between sources; Editorial revisions

issues: EE revisions , Cautionary accidentals

b. 6-10

composition: Op. 28 No. 20, Prelude in C minor

..

In the main text we add cautionary naturals before the F-f octave in b. 6 and 10.

category imprint: Editorial revisions

b. 6

composition: Op. 28 No. 13, Prelude in F♯ major

Minim & rest in A (→FEEE)

Dotted minim in FC (→GE)

..

The longer chord in the 2nd half of the bar must be Fontana's mistake.

category imprint: Differences between sources

issues: Errors of FC