The Book of the Commencement of the Prayer
11/51. Chapter:
The Prostration in: "When the heaven is split asunder"
Sunan an-Nasai
أَخْبَرَنَا قُتَيْبَةُ، عَنْ مَالِكٍ، عَنْ عَبْدِ اللَّهِ بْنِ يَزِيدَ، عَنْ أَبِي سَلَمَةَ بْنِ عَبْدِ الرَّحْمَنِ، أَنَّ أَبَا هُرَيْرَةَ، قَرَأَ بِهِمْ { إِذَا السَّمَاءُ انْشَقَّتْ } فَسَجَدَ فِيهَا فَلَمَّا انْصَرَفَ أَخْبَرَهُمْ أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم سَجَدَ فِيهَا .
It was narrated from Abu Salamah bin Abdur- Rahman that: Abu Hurairah (led them in prayer and) recited: "When the heaven is split asunder." and prostrated during it. When he had finished praying, he told them that the Messenger of Allah (ﷺ) had prostrated during it.
Reference : Sunan an-Nasa'i 961In-book reference : Book 11, Hadith 86English translation : Vol. 2, Book 11, Hadith 962