in 
In all sources related to the publication process of the Etude (A and editions), the bar is provided with a pair of dynamic hairpins. However, the sources or their groups differ quite significantly, as far as the range of the signs is concerned. In the main text, we give the signs of FE, showing similarity to the indications in analogous bar 19. Chopin could have written such hairpins in the base text to FE or added while proofreading this edition. GE2 (→GE3) also include a similar version, probably revised on the basis of comparison with bar 19.
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category imprint: Interpretations within context; Differences between sources
issues: Scope of dynamic hairpins
notation: Articulation, Accents, Hairpins