The cautionary naturals before c1 in the L.H. were added in bars 9 and 13 in one of the last proofreadings of FE (→GE). They are also included in EE, except for the overlooked in bar 13 in EE2. The manuscripts do not include any signs in these places.
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category imprint: Differences between sources
issues: Cautionary accidentals, EE inaccuracies, Authentic corrections of FE
notation: Pitch