Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi)
حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ سَعِيدٍ، حَدَّثَنَا مُحَمَّدُ بْنُ بَكْرٍ، حَدَّثَنَا ابْنُ جُرَيْجٍ، أَخْبَرَنِي مُوسَى بْنُ عُقْبَةَ، عَنْ نَافِعٍ، أَخْبَرَهُ ابْنُ عُمَرَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم حَلَقَ فِي حَجَّةِ الْوَدَاعِ وَأُنَاسٌ مِنْ أَصْحَابِهِ وَقَصَّرَ بَعْضُهُمْ.Narrated Ibn `Umar:During Hajjat-ul-Wada`, the Prophet (ﷺ) and some of his companions got their heads shaved while some of his companions got their head-hair cut short
From Sahih al-Bukhari, whose reports the scholars accept as authentic.