مصنف ابن ابي شيبه
Musannaf Ibn Abi Shaybah
سجود السهو والعمل في الصلاةProstration of Forgetfulness and Actions in Salah
الرجل يسبق بالركعة (من الصلاة) وعلى الإمام سهوIf a Follower Misses Part of the Imam's Prayer, He Should Make It Up Like the Imam
Hadith 4633
٤٦٣٣ - حدثنا ابن إدريس عن هشام عن ابن سيرين والحسن قال ابن سيرين: يقضي ثم يسجد.
Hazrat Ibn Sirin says that first he should complete his prayer and then perform the prostration of forgetfulness (sajdah sahw). Hasan says that first he should perform the prostration of forgetfulness and then complete his prayer.
