In A the c3 quaver at the beginning of the bar is written also as the 1st note of the semiquaver triplet of the bottom voice. In the proofreading of FE1 Chopin replaced it with a rest. The traces of performed changes in print allow to state that the actual proofreading included also a2, which the engraver of FE saw in A (according to us, unjustifiably).
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category imprint: Differences between sources; Corrections & alterations
issues: Authentic corrections of FE, Uncertain notes on ledger lines
notation: Pitch