Trill endings in the form of a double grace note are to be found in FEF in all three analogous places (bars 26, 28, and 30), while in PE only in the first two. Regardless of whether the lack of ending in bar 30 appeared still in [A], or if it is a mere engraver's oversight, it seems to be highly unlikely that a trill in this place should be performed differently than in the previous two.
Lack of endings in GEF proves that Fontana introduced last corrections into FEF after GEF had already been printed.
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category imprint: Differences between sources
issues: Fontana's revisions
notation: Ornaments