The indication in FE (→GE1→GE2→GE3→GE4, →EE) seems to concern only the semiquavers in the R.H. According to us, as it is hard to suppose that the long resounding octaves in the L.H. were to be played in different dynamics, it should be assumed as an inaccuracy of the notation. A respective change was also introduced in GE5. See also bar 45.
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category imprint: Interpretations within context; Differences between sources
issues: Centrally placed marks
notation: Verbal indications