However, the largest part of the collection--although they are not often exhibited--is formed by rare books and documents, such as the enormous Qing dynasty compendium Si Ku Quan Shu. These comprise close to 540,000 items.
而圖書文獻如四庫全書和善本圖書等，雖不是展覽場上的常客，卻庫存最多，有五十四萬多件。