Beethoven's three sets of cello variations comprise the 12 Variations on a Theme from Handel's Oratorio Judas Maccabeus (WoO 45), the 12 Variations on the theme Ein Mädchen oder Weibchen (Op. 66) from Mozart's opera Die Zauberflöte and the 7 Variations on the duet Bei Männern, welche Liebe fühlen (WoO 46), also from Die Zauberflöte.
These works have existed in many different editions, some of which have from time to time been (tacitly) reprinted with corrections to keep up to date with the latest scholarship. This edition, however, is the first to give all Beethoven's rhythms in the cello part correctly. Beethoven's autograph manuscript of Op. 66 is lost; the critical commentary (English) includes a complete facsimile of the cello part from the only surviving source (the first edition), illustrating the various problems encountered in determining the best musical text.