كتاب الصلاة
2  
The Book of Prayer
Bulugh al-Maram 338
Narrated 'Umar (RA):
The Prophet (ﷺ) said: "There is no (prostrations of) forgetfulness for one who is led (in prayer) by an Imam, but when the Imam forgets, both should then make prostrations due to forgetfulness." [al-Bazzar and al-Baihaqi reported it through a weak chain of narrators].
وَعَنْ عُمَرَ رَضِيَ اَللَّهُ عَنِ النَّبِيِّ ‏- صلى الله عليه وسلم ‏-قَالَ : { لَيْسَ عَلَى مَنْ خَلَفَ اَلْإِمَامَ سَهْوٌ فَإِنْ سَهَا اَلْإِمَامُ فَعَلَيْهِ وَعَلَى مَنْ خَلْفَهُ" } رَوَاهُ اَلْبَزَّارُ وَالْبَيْهَقِيُّ بِسَنَدٍ ضَعِيفٍ .‏ 1
Reference : Bulugh al-Maram 338
In-book reference : Book 2, Hadith 338
English translation : Book 2, Hadith 333
Hadith Text
Reference