Nahj al-Balāgha
Hadith 1193مِنْ عَبْدِ اللهِ عَلِيٍّ أَمِيرِ الْمُؤْمِنِينَ إلَى أَهْلِ الْكُوفَةِ، جَبْهَةِ الْأَنْصَارِ وَسَنَامِ الْعَرَبِ.
From the servant of Allāh, ‘Alī, the Commander of the faithful, to the people of Kūfah who are foremost among the supporters and chiefs of the Arabs.