The Book of Prayers (Kitab Al-Salat)
Muslim :: Book 4 : Hadith 1649
Abu Sa'id reported that they (some of the Companions) of the Holy Prophet (may peace be upon him) asked the Apostle of Allah (may peace be upon him) about Witr. He said: Observe Witr before morning.
Source materials are from the University of Southern California MSA site|
Hadith eBooks converted from Imaan Star