Sahih Al Bukhari Hadith Number 1095

Narrated Nafi`: Ibn `Umar (while on a journey) used to offer the prayer and the witr on his mount (Rahila). He said that the Prophet (peace be upon him) used to do so.

18  Shortening the Prayers (At-Taqseer)
Hadith number 1095
Volume no 2
Chapter: 7 ( To offer Nawafil on the back of animals)