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b. 18-29

composition: Op. 2, Variations, complete

category imprint: Differences between sources; Corrections & alterations

b. 19

composition: Op. 2, Variations, complete

mezza voce in A (→GEEE,FESB)

No indication in FE

..

In the main text we include the change Chopin ordered while proofreading FE1 – there are visible traces of removal of mezza voce in print.

category imprint: Differences between sources; Corrections & alterations

issues: Authentic corrections of FE

b. 19

composition: Op. 2, Variations, complete

e3-g3 in sources, literal reading

e3-g3 suggested by the editors

..

Even though none of the sources features an accidental to the top note of the last semiquaver, the use of g3 is much more likely, considering the melodic and harmonic context. Overlooked accidentals in such situations are one of Chopin's most frequent mistakes, cf., e.g. the Etude in F minor, Op. 25 No. 2, b. 4 or the Impromtu in A, Op. 29, b. 3 and 71. 

category imprint: Differences between sources

issues: Omissions to cancel alteration , Errors of A

b. 19

composition: Op. 2, Variations, complete

Repeated thirds in #ApI

Single notes in A (→GEFE,EE,FESB)

category imprint: Differences between sources; Corrections & alterations; Source & stylistic information

issues: Chopin's hesitations , Main-line changes

b. 20

composition: Op. 2, Variations, complete

c in A, FE & GE2 (→GE3,FESB)

e in GE1 (→EE)

..

The version of GE1 (→EE) must be a Terzverschreibung, corrected in GE2 (→GE3,FESB) and in FE1, probably by Chopin.

category imprint: Differences between sources

issues: Errors in GE , GE revisions , Authentic corrections of FE