The natural lowering C
to C was written in FED in pencil probably by Chopin. It does not look like a correction of a previous error, therefore, one can consider this version as an authentic variant. In the main text we add a cautionary 
before C; the addition was already introduced in GE and EE4.
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category imprint: Differences between sources; Editorial revisions; Corrections & alterations
issues: Annotations in teaching copies, Annotations in FED
notation: Pitch