Sunan an-Nasa'i 829
سنن النسائي#829SahihIt was narrated that Abu Ishaq said:"I heard 'Abdullah bin Yazid delivering a Khutbah. He said: 'Al-Bara, who was no liar,told us that when they prayed with the Messenger of Allah (ﷺ) would raise his head from bowing and they would remain standing until they saw him prostrate, then they would prostrate
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 10:53