Prayer (Kitab Al-Salat): Detailed Injunctions about Witr
Dawud :: Book 8 : Hadith 1438
Narrated Abdullah ibn Abbas:
The Apostle of Allah (peace_be_upon_him) recited the supplication (Qunut) daily for a month at the noon, afternoon, sunset, night and morning prayers. When he said: "Allah listens to him who praises Him" in the last rak'ah, invoking a curse on some clans of Banu Sulaym, Ri'l, Dhakwan and Usayyah, and those who were standing behind him said: Amen.