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b. 56

composition: Op. 10 No 12, Etude in C minor

c2 in A (→FEEE,GE1GE2)

d2 in GE3 (→GE4)

..

The d2 note in the 1st chord is most probably a result of a mistake of the engraver of GE3 (→GE4).
The  added before c2 in FE (→GE1,EE) also seems to be a mistake.

category imprint: Differences between sources

issues: Errors in GE

b. 57-59

composition: Op. 10 No 12, Etude in C minor

No fingering in A (→FEGE)

Fingering in EE

..

We do not include the fingering added by Fontana in EE. It generally does not differ from the fingering based on the one by Chopin added by Fontana in analogous bars 17-19.

category imprint: Differences between sources

issues: EE revisions

b. 57

composition: Op. 10 No 12, Etude in C minor

No teaching fingering

Numeral '4' in FED

..

Chopin added the fingering digit in FED.

category imprint: Differences between sources

issues: Annotations in teaching copies , Annotations in FED

b. 57

composition: Op. 10 No 12, Etude in C minor

No ties in A

Ties in FE (→GE,EE

..

Lack of the hold of the e1-e2 octave in A is most probably Chopin's mistake, corrected in FE (→GE,EE).

category imprint: Differences between sources

issues: Errors of A , Authentic corrections of FE

b. 57

composition: Op. 10 No 12, Etude in C minor

Dotted minim in A (→FEGE) & EE4

Minim in EE3

Our suggestion

..

In the main text we separate the c2 note from the chord, as in this case Chopin's simplified notation may be unclear, e.g., considered to be erroneous, as it probably occurred in EE3.

category imprint: Differences between sources; Editorial revisions

issues: EE revisions , Different values of chord components , Errors in EE