Lack of slur is a patent error of GE1, corrected in GE2 (→GE3). In FE and EE the slur was placed under the notes, which was certainly an arbitrary decision of the engraver – in both editions the stems of the notes are directed upwards, while the slur was routinely moved to the side of note heads.
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category imprint: Differences between sources; Source & stylistic information
issues: EE revisions, Placement of markings, Errors in GE, GE revisions, FE revisions
notation: Slurs