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b. 167

composition: Op. 50 No. 3, Mazurka in C♯ minor

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On the 2nd beat of the bar in AI, there are no naturals lowering f to f and d1 to d1. Chopin's inaccuracy is proven by an analogy with b. 159, by the presence of d both in the D major key in b. 165 and F major key starting from the 2nd beat of b. 166 and, above all, by the presence of these naturals in all the remaining sources.

category imprint: Interpretations within context; Differences between sources

issues: Accidentals in different octaves , Omission of current key accidentals

b. 168

composition: Op. 50 No. 3, Mazurka in C♯ minor

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In the main text we add a cautionary  before d. The accidental was also added in EE.
Following the example of GE, we omit the  before a1 at the end of the bar, which was unnecessarily repeated in the remaining sources.

category imprint: Differences between sources; Editorial revisions

issues: Cautionary accidentals , Last key signature sign

b. 170

composition: Op. 50 No. 3, Mazurka in C♯ minor

..

The last R.H. bottom voice crotchet in EE is a1, which is a mistake. It was most probably EE in which this patent Terzverschreibung was committed, since FE does not reveal traces of corrections in this place.

category imprint: Interpretations within context; Differences between sources

issues: Errors in EE , Terzverschreibung error

b. 170

composition: Op. 50 No. 3, Mazurka in C♯ minor

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The R.H. bottom voice crotchet on the 2nd beat of the bar is written in AI as f1. Chopin changed it to g1 while writing AF – one can see a crossed-out f1 next to the note.
In EE – just like in b. 164 – cautionary naturals were added before b and a.

category imprint: Differences between sources

issues: EE revisions , Enharmonic corrections

b. 171-172

composition: Op. 50 No. 3, Mazurka in C♯ minor

AI version

AF (→FE)

Same with  a2 in EE

..

Without access to [AG], it is impossible to determine whether and which version Chopin considered to be final. The general concordance between AI and GE suggests that this version was created first; however, even if it was the case, it does not mean that an alternative idea – the version of AF – was already the final word, since there are numerous examples, supported by sources, of returns to original versions, which was poignantly described by George Sand. Therefore, having a choice between two equal authentic versions, in the main text we give the text of GE, which is the principal source adopted for the entire op. 50.  

category imprint: Differences between sources; Corrections & alterations

issues: Chopin's hesitations , Accompaniment changes , Enharmonic corrections