Abu Dawud
Prayer
Book Number: 002 / Hadith Number: 1413
Narated By Kharijah ibn Hudhafah al-Adawi : The Apostle of Allah (pbuh) came out to us and said: Allah the Exalted has given you an extra prayer which is better for you then the red camels (i.e. high breed camels). This is the witr which Allah has appointed for you between the night prayer and the daybreak.