The effect of diminuendo, indicated by Chopin in these bars, results from the previous 
or 
at the beginning of bar 19. As in the main text we adopt after FE and EE, we give dim. also on the basis of these sources (at the end of bar 19). In A Chopin moved this indication half a bar later (to bar 20); this correction could have been performed still before introducing instead of .
The total or partial lack of dashes marking the range of diminuendo is almost certainly a result of an inaccurate reproduction of notation of the handwritten base texts by the engravers.
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category imprint: Differences between sources; Corrections & alterations
issues: Corrections in A
notation: Verbal indications