أَخْبَرَنَا عَمْرُو بْنُ عَلِيٍّ، قَالَ حَدَّثَنَا يَحْيَى، قَالَ حَدَّثَنَا قُرَّةُ بْنُ خَالِدٍ، عَنْ مُحَمَّدِ بْنِ سِيرِينَ، عَنْ أَبِي هُرَيْرَةَ، قَالَ سَجَدَ أَبُو بَكْرٍ وَعُمَرُ - رضى الله عنهما - فِي ‏{‏ إِذَا السَّمَاءُ انْشَقَّتْ ‏}‏ وَمَنْ هُوَ خَيْرٌ مِنْهُمَا ‏.‏

It was narrated that Abu Hurairah said: "Abu Bakr and Umar prostrated during: 'When the heaven is split asunder,' as did the one who was better than them (the Prophet (PBUH)). " Translation Not Available

Book Ref: Sunan An Nisai Book 11 Hadith 965
Web Ref:  Sunan An Nisai Vol 2 Book 11 Hadith 966