Sahih al-Bukhari 4271
Sahih al-Bukhari · Book 64: Military Expeditions led by the Prophet (pbuh) (Al-Maghaazi) · The dispatch of Usama bin Zaid to Al-Huraqat
Narrated Salama (in another narration):
وَقَالَ عُمَرُ بْنُ حَفْصِ بْنِ غِيَاثٍ حَدَّثَنَا أَبِي ، عَنْ يَزِيدَ بْنِ أَبِي عُبَيْدٍ ، قَالَ سَمِعْتُ سَلَمَةَ ، يَقُولُ غَزَوْتُ مَعَ النَّبِيِّ صلى الله عليه وسلم سَبْعَ غَزَوَاتٍ، وَخَرَجْتُ فِيمَا يَبْعَثُ مِنَ الْبَعْثِ تِسْعَ غَزَوَاتٍ، عَلَيْنَا مَرَّةً أَبُو بَكْرٍ، وَمَرَّةً أُسَامَةُ.
I fought seven Ghazwat (i.e. battles) along with the Prophet (ﷺ) and also fought in nine battles, fought by armies sent by the Prophet (ﷺ) . Once Abu Bakr was our commander and another time, Usama was (our commander).