EE
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b. 41
The in tempo indication was most probably added as part of the Chopinesque proofreading of FE. There is a similar situation in bar 57. The change of the preposition from in to a was an arbitrary decision of the engraver/reviser of EE.
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category imprint: Differences between sources
issues: EE revisions, Authentic corrections of FE
notation: Verbal indications