In b. 149 and 151 the autographs are devoid of cautionary accidentals. In the first stage of proofreading of FE (→EE) a 
was added before b in b. 151; the accidental is also present in GE. In the second stage of proofreading of FE a before b was also added in b. 149; moreover, a 
was repeated before the R.H. b
note on the 3rd beat of the bar.
We include both naturals in the main text.
Compare the passage in the sources »
category imprint: Differences between sources
issues: Cautionary accidentals, Authentic corrections of FE, FE revisions
notation: Pitch