ENOfficial
Narrated Sulaiman Ash-Shaibani: I heard Ash-Shu`bi saying, "I was told by a man who had passed with the Prophet (p.b.u.h) by a grave that was separate from the other graves that he (the Prophet (ﷺ) ) led them in the prayer and they prayed behind him." I said, "O Abu `Amr! Who narrated that to you?" He replied, "Ibn `Abbas."
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا حَجَّاجُ بْنُ مِنْهَالٍ، حَدَّثَنَا شُعْبَةُ، قَالَ حَدَّثَنِي سُلَيْمَانُ الشَّيْبَانِيُّ، قَالَ سَمِعْتُ الشَّعْبِيَّ، قَالَ أَخْبَرَنِي مَنْ، مَرَّ مَعَ النَّبِيِّ صلى الله عليه وسلم عَلَى قَبْرٍ مَنْبُوذٍ فَأَمَّهُمْ وَصَلَّوْا خَلْفَهُ. قُلْتُ مَنْ حَدَّثَكَ هَذَا يَا أَبَا عَمْرٍو قَالَ ابْنُ عَبَّاسٍ ـ رضى الله عنهما ـ.
sunnah.com