In A1 one can see a correction of the last semiquaver in the 1st half of the bar, which was initially written as c
3. Chopin then crossed out the 
and enlarged the notehead so that it reaches the line above and looks like d3. The original version is preserved in b. 48.
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category imprint: Corrections & alterations; Source & stylistic information
issues: Corrections in A, Deletions in A, Enharmonic corrections
notation: Pitch