Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ، حَدَّثَنَا سُفْيَانُ، أَخْبَرَنَا مَنْصُورٌ، عَنْ أَبِي وَائِلٍ، عَنْ عَبْدِ اللَّهِ، قَالَ كُنَّا نَقُولُ لِلْحَىِّ إِذَا كَثُرُوا فِي الْجَاهِلِيَّةِ أَمِرَ بَنُو فُلاَنٍ. حَدَّثَنَا الْحُمَيْدِيُّ حَدَّثَنَا سُفْيَانُ وَقَالَ أَمِرَ.Narrated `Abdullah:During the Pre-Islamic period of ignorance if any tribe became great in number, we used to say, "Amira the children of so-and-so." Narrated Al-Humaidi: Sufyan narrated to us something and used the word 'Amira
From Sahih al-Bukhari, whose reports the scholars accept as authentic.