The piece consists of 64 sections of four bars, and we have regarded the sections as variations. The variations appear in formal units consisting of one, two or three variations. There are: 5 single variations, 25 double variations, 3 triple variations, altogether 33 formal units. The two parts containing arpeggios (23-31. and 51-52.) are published in a written out form. Our approach dispenses with tradition and is rooted in a consideration of the work as a whole. In the case of the variations with arpeggios we took into account the changes in the number of voices and the situation of the rhythmic span of the overall form.