Jami` at-Tirmidhi 364
جامع الترمذي#364SahihAsh-Sha'bi narrated:"Al-Mughirah bin Shu'bah led us in Salat, and he continued after the two Rak'ah, so the people said: 'Subhan Allah' and he said: 'Subhan Allah' to them. When he finished his Salat he said the Taslim then performed two prostrations of As-Sahw while he was sitting. Then he narrated to them that Allah's Messenger did the same with them as he had done
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 2:216