In FC one can see corrections of the 10th and 13th semiquavers in both bars and of the 5th and 8th semiquavers in bar 43. Everywhere, c2(3) notes were erased and b1(2) added. It is most probably an auto-correction of the copyist, which is proved by the typeface of naturals before the added notes and lack of visible corrections (although they are not entirely excluded) in the notation of three b notes. On the other hand, if the text was clear in the copied manuscript (probably [A]), without corrections, such a significant mistake of such an experienced copyist as Fontana (after all, a professional composer and pianist) seems to be inexplicable. Therefore, what we see may be a preserved trace of the authentic original version of these bars, in which the middle note in the R.H. was always c (in different octaves).
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category imprint: Corrections & alterations; Source & stylistic information
issues: Accompaniment changes, Authentic corrections of FC
notation: Pitch