Sonatas Op. 35, 58 (Series A, Vol. X) Edition by Jean Ekier
''Sonatas'' (beside the ballades, scherzos and the ''Fantasia in F minor'') form a group of works from the period of synthesis, characterised by masterly technique and the most intense expression. Volume X of the National Edition contains two ''Sonatas'' by Chopin. Of the variants in musical notation, those designated ''ossia'' were marked in this way by Chopin himself or inscribed in his hand in his pupils' copies, while those without this indication result from textual divergences in authentic copies or from difficulties in reading the text in an unambiguous way.
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