In A (→GE) the crotchet of the bottom voice is written as a g2. Similarly, the bottom note of the 3rd quaver is a g1. While proofreading FE (→EE), Chopin changed the notation of both notes to a2(1), in accordance with the way in which he wrote all subsequent appearances of similar bars.
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category imprint: Differences between sources; Corrections & alterations
issues: Enharmonic corrections, Authentic corrections of FE
notation: Pitch