كتاب الصلاة
2  
The Book of Prayer
Bulugh al-Maram 309
Narrated Ibn 'Abbas (RA):
Allah's Messenger (ﷺ) used to teach us a supplication to say in the Qunut of the morning prayer. [al-Baihaqi reported it and there is a weakness in its chain of narrators].
وَلِلْبَيْهَقِيِّ عَنْ اِبْنِ عَبَّاسٍ ‏-رَضِيَ اَللَّهُ عَنْهُمَا‏- : { كَانَ رَسُولُ اَللَّهِ ‏- صلى الله عليه وسلم ‏-يُعَلِّمُنَا دُعَاءً نَدْعُو بِهِ فِي اَلْقُنُوتِ مِنْ صَلَاةِ اَلصُّبْحِ } وَفِي سَنَدِهِ ضَعْفٌ .‏ 1
Reference : Bulugh al-Maram 309
In-book reference : Book 2, Hadith 309
English translation : Book 2, Hadith 307
Hadith Text
Reference