Lit. sheets, refering to the sheets that recorded the Qur'anic verses, and the portions of scriptures earlier revealed, eg. Abraham and Moses.
Some Muslims claim that the Bible has been corrupted because it talks about books that are no longer extent:
So the sun stood still, and the moon stopped, till the nation avenged itself on its enemies, as it is written in the Book of Jashar. The sun stopped in the middle of the sky and delayed going down about a full day. (Joshua 10:13)The first problem, is that nowhere in the Bible does it say that the Book of Jashar is supposed to be in the Bible. More likely than not, it was an account of the events that circulated when the book of Joshua was written.
Secondly, the Qur'an also speaks of missing inspired books. In al-A`la 87:18-19, we read:
Lo! This is in the former scrolls. The Books of Abraham and Moses.Muslims acknowledge that the books of Abraham are no longer with us. Does that mean that the Qur'an is corrupted?(Inna hatha lafee alssuhufi al-oola Suhufi ibraheema wamoosa)