This is an interesting publication. These attractive studies by Lindpaintner (from Op 126) have had a second flute part added to them by Altes, thus turning them into very appealing duets. The second parts do not necessarily cover the same technical issues as the first parts, nor are they mere accompaniments so both players have a great deal of independence. Some of the duets are quite substantial, so these are more than just sightreading practice and would certainly be in the performance category. Pricey I know, but worth it.
Performance duration (approx): 2'40