Not only is the 80-page document a working manuscript for the only piano version of a major work by Beethoven, it is one of his few compositions for a piano duet.

• 这份长达80页的手稿不仅是贝多芬的一部主要作品的唯一钢琴演奏版，也是他创作的为数不多的钢琴二重奏乐谱之一。