The continuous slur possibly results from conviction by both Fontana in FC (→GE) and the engraver of FE (→EE) that the cause of slurs in A being separated is just another pause in the ink feed to the tip of the quill, as in b. 61-62 (as well as 66). In the editors' opinion the shape of the slurs rather indicates that they are intentionally separate.
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category imprint: Differences between sources
issues: Inaccuracies in FE, Inaccuracies in FC
notation: Slurs