Sunan Ibn Majah 1243
سنن ابن ماجه#1243SahihIt was narrated from Anas bin Malik that the Messenger of Allah (ﷺ) used to recite Qunut in the Subh prayer, and he used to supplicate in it against one of the Arab tribes for a month, then he stopped doing so
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Fouad Abd al-BaqiSahih
Shuaib Al ArnautSahih
Zubair Ali ZaiSahih - Bukhari And Muslim
In-book reference: 5:441