مصنف ابن ابي شيبه
Musannaf Ibn Abi Shaybah
سجود السهو والعمل في الصلاةProstration of Forgetfulness and Actions in Salah
من كان يرخص (في) أن يلحظ و يلتفتIf Someone Makes More Than One Mistake in Salah, What Should He Do?
Hadith 4625
٤٦٢٥ - حدثنا جرير عن مغيرة عن إبراهيم قال: إذا سها الإمام فلم يدر كم صلى نظر ما يصنع من خلفه.
Ibrahim says that if the imam makes a mistake and does not know how many units of prayer he has performed, he should look at the person standing behind him to see what he is doing.
