Citation Hunt

The Wikipedia snippet below is not backed by a reliable source. Can you find one?

Click I got this! to go to Wikipedia and fix the snippet, or Next! to see another one. Good luck!

In page History of the Quran:

"

According to Islamic tradition the process of canonization ended under the third caliph, Uthman ibn Affan (r. 23/644–35/655), which was about twenty years after the death of Muhammad. The Qur'anic canon is the form of the Quran as recited and written in which it is religiously binding for the Muslim community. This canonical corpus is closed and fixed in the sense that nothing in the Quran can be changed or modified.[1] (The date—round 650 CE—is vague because is was not recorded by early Arab annalists.)[2]