The naturals returning a1, d2 and f2 in bars 9 and 13 are inaccurately written in some of the sources. In CLI they are totally absent, although in bar 13 the sign returning d2 is before the last semiquaver in the lower voice. In FEcor Chopin added them only in bar 9, yet, eventually, he also added the 
returning f2 in bar 13 in FE (→EE2). In GE1 only the sign returning d2 in bar 13 is missing. The remaining sources have the correct notation.
Compare the passage in the sources »
category imprint: Interpretations within context; Differences between sources
issues: EE revisions, Errors in FE, Omissions to cancel alteration, GE revisions, Errors of CLI
notation: Pitch