(61) باب بَغْلَةِ النَّبِيِّ صلى الله عليه وسلم الْبَيْضَاءِ
Narrated Al-Bara:
that a man asked him. "O Abu '`Umara! Did you flee on the day (of the battle) of Hunain?" He replied, "No, by Allah, the Prophet (ﷺ) did not flee but the hasty people fled and the people of the Tribe of Hawazin attacked them with arrows, while the Prophet (ﷺ) was riding his white mule and Abu Sufyan bin Al-Harith was holding its reins, and the Prophet (ﷺ) was saying, 'I am the Prophet (ﷺ) in truth, I am the son of `Abdul Muttalib.' "
Reference: Sahih al-Bukhari 2874
In-book reference: Book 56, Hadith 90
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 4, Book 52, Hadith 126