The absence of a dynamic indication is most probably an oversight of the engraver of FE. The addition of 
in EE was performed probably on the basis of a comparison with bar 91. In turn, the 
indication written in FES, in spite of the fact that there are no reasons to question its authenticity, is, however, most probably only an ad hoc lesson comment, correcting the absence of the dynamic indication in FE. Therefore, we do not consider it to be an expression of a general change of the dynamic concept of this introduction.
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category imprint: Differences between sources; Corrections & alterations
issues: Annotations in teaching copies, EE revisions, Errors in FE, Annotations in FES, Authentic post-publication changes and variants
notation: Verbal indications