In A the dynamic marks – 
and particularly 
– in bars 51-53, 60 and 62-63 are written only on the 4th beat of the bar, sometimes on 
marks. According to us, it is an example of use of an earlier notation convention by Chopin – see bars 10-12. In FE (→GE,EE) only one of the indications was reproduced in accordance with A (bar 52), some of them were overlooked (in separately discussed bars 61-62) and the remaining ones were arranged in such way so they concern entire octave motifs pursuant to the currently binding notation rules. Cf. the remarks concerning marks in bars 51-63.
Compare the passage in the sources»
category imprint: Interpretations within context; Differences between sources
issues: Authentic corrections of FE, Centrally placed marks
notation: Verbal indications