Musnad Ahmad 36676

Arabic

حَدَّثَنَا إِسْحَاقُ بْنُ عِيسَى بْنِ الطَّبَّاعِ، عَنْ أَبِي مَعْشَرٍ، قَالَ وَقُتِلَ عُثْمَانُ رَضِيَ اللَّهُ عَنْهُ يَوْمَ الْجُمُعَةِ لِثَمَانِ عَشْرَةَ مَضَتْ مِنْ ذِي الْحِجَّةِ سَنَةَ خَمْسٍ وَثَلَاثِينَ وَكَانَتْ خِلَافَتُهُ ثِنْتَيْ عَشْرَةَ سَنَةً إِلَّا اثْنَيْ عَشَرَ يَوْمًا‏.‏

Translation

Narrated by It was narrated that Abu Ma`shar said:

`Uthman (رضي الله عنه) was killed on the eighteenth of Dhul-Hijjah 35 AH, His caliphate lasted twelve years less twelve days.

Reference