Sunan an-Nasa'i 968
سنن النسائي#968SahihIt was narrated that Abu Rafi' said:"I prayed Isha' prayer- meaning Al-'Atamah behind Abu Hurairah and he recited: 'When the heaven is split asunder' and prostrated during it. When he had finished praying, I said: 'O Abu Hurairah, (this is) a prostration that we are not used to.' He said: 'Abu Al-Qasim (ﷺ) did this prostration and I was (praying) behind him, and I will continue to do this prostration until I meet Abu Al-Qasim
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: 11:93