Standardization of the Mushaf Under Caliph Uthman (RA)

"During the caliphate of Uthman ibn Affan (RA) around 25 AH (646 CE), companion Hudhayfah ibn al-Yaman (RA) noticed regional pronunciation differences among new Muslims in the frontier provinces of Armenia and Azerbaijan. Caliph Uthman (RA) formed a committee of four leading scholars—headed by Zayd ibn Thabit (RA)—to produce official master copies from the Suhuf kept with Hafsah bint Umar (RA) and distribute them to the major Islamic centers along with trained reciters."