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Pitch

b. 33

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

..

A originally had F as the first quaver.

category imprint: Corrections & alterations; Source & stylistic information

issues: Corrections in A , Deletions in A , Accompaniment changes , Bass register changes

b. 42-44

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

..

Chopin used in these bars cautionary naturals before a(1) and g(1) in b. 42 and d(1) in b. 43. FC (→GE) and EE also added a  before G in b. 44. In the main text we include all the above naturals; moreover, we suggest naturals before d1(2) in b. 42 and g(1) in b. 43.

category imprint: Differences between sources; Editorial revisions; Source & stylistic information

issues: EE revisions , Cautionary accidentals , Fontana's revisions

b. 43

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

category imprint: Differences between sources

issues: Errors in EE

b. 44

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

..

In FE the  in the L.H. part is before the top note of the third on the 3rd quaver in the bar, which results in A-c. The patent mistake was corrected in EE. The remaining sources also contain the correct text.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Errors in FE

b. 45-49

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

..

In the main text we add cautionary naturals before g and G in b. 45, 47 and 49. See b. 42-43.

category imprint: Editorial revisions