Hadhrat Anas bin Malik R.A narrates,
"Hadhrat Hudhaifa bin Al-Yaman came to Hadhrat Uthman R.A at the time when the people of Sham and the people of Iraq were waging war to conquer Arminya and Azarbaijan. Hadhrat Hudhaifa R.A. was afraid of their (the people of Sham and Iraq) differences in the recitation of the Qur'an, so he said to Hadhrat Uthman R.A., "O Chief of the Believers! Save this nation before they differ about the Book (Qur'an) as Jews and the Christians did before."
So Hadhrat Uthman R.A.sent a message to his daughter Hafsa R.A, saying, "Send us the manuscripts of the Qur'an so that we may compile the Qur'anic materials in perfect copies and return the manuscripts to you."
Hadhrat Hafsa R.A. sent it to Hadhrat Uthman R.A. He then ordered Hadhrat Zaid bin Thabit R.A, Hadhrat Abdullah bin Zubair R.A, Hadhrat Said bin Al-As R.A and Hadhrat Abdur Rahman bin Harith bin Hisham R.A. to rewrite the manuscripts in perfect copies.
Hadhrat Uthman R.A. said to the three Quraishi men, "In case you disagree with Zaid bin Thabit on any point in the Qur'an, then write it in the dialect of Quraish, the Qur'an was revealed in their tongue."
They did so, and when they had written many copies, Hadhrat Uthman R.A returned the original manuscripts to Hafsa R.A. He sent a copy of what they had copied to every Muslim province, and ordered that all the other Qur'anic materials, whether written in fragmentary manuscripts or whole copies, be burnt.
Hadhrat Said bin Thabit R.A. added, "A verse from Surah Ahzab was missed by me when we copied the Qur'an Shareef, and I used to hear Allah's Messenger (Sallallahu alaihi wasallam) reciting it. So we searched for it and found it with Khuzaimah bin Thabit Al-Ansari R.A.
(That Verse was), "Among the Believers are men who have been true in their Covenant with Allah." --(33.23) --Bukhari.