(53) باب الرِّكَابِ وَالْغَرْزِ لِلدَّابَّةِ
Narrated Ibn'`Umar:
When the Prophet (ﷺ) put his feet in the stirrup and the she-camel got up carrying him he would start reciting Talbiya at the mosque of Dhul-Hulaifa.
Reference: Sahih al-Bukhari 2865
In-book reference: Book 56, Hadith 81
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 4, Book 52, Hadith 117