The mark, which bears all characteristics of a long accent in FE, was interpreted in the remaining editions as a 
hairpin. It is evidenced by the fact that the mark was being extended, which is particularly clear in GE2 (→GE3) and EE; the aim could have been to partially adjust the mark to the longer 
mark in the preceding bar.
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category imprint: Differences between sources
issues: Long accents, EE revisions, Inaccuracies in GE, GE revisions
notation: Articulation, Accents, Hairpins