‏الصلاة : Hadeeth No:1442 Anas reported that the Messenger of Allaah (sallAllaahu alayhi wa sallam) observed Qunut for one month invoking curse upon some tribes of Arabia (those who were responsible for the murders in Bi'r Ma'una and Raji'), but then abandoned it....

‏الصلاة : Hadeeth No:774 This hadith has also been transmitted by Ma'mar from al-Zuhri with the same chain of transmitters with the addition of these words:" and something more"....