Virtues and Merits of the Prophet (pbuh) and his Companions
وَقَالَ لَنَا قَبِيصَةُ أَخْبَرَنَا سُفْيَانُ، عَنْ حَبِيبِ بْنِ أَبِي ثَابِتٍ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ لَمَّا نَزَلَتْ {وَأَنْذِرْ عَشِيرَتَكَ الأَقْرَبِينَ} جَعَلَ النَّبِيُّ صلى الله عليه وسلم يَدْعُوهُمْ قَبَائِلَ قَبَائِلَ.Narrated Ibn `Abbas: When the Verse:-- 'And warn your tribe of near kindred' (26.214). was revealed, the Prophet (ﷺ) started calling every tribe by its name
From Sahih al-Bukhari, whose reports the scholars accept as authentic.