Muwatta Imam Malik Book of Burials, Hadith 8
Yahya related to me from Malik from Ibn Shihab that the Messenger of Allah ﷺ and Abu Bakr and Umar as well as the khalifas up until this time and Abdullah ibn Umar, would walk in front of the bier.
حَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنِ ابْنِ شِهَابٍ، أَنَّ رَسُولَ اللَّهِ ﷺ وَأَبَا بَكْرٍ وَعُمَرَ كَانُوا يَمْشُونَ أَمَامَ الْجَنَازَةِ وَالْخُلَفَاءُ هَلُمَّ جَرًّا وَعَبْدُ اللَّهِ بْنُ عُمَرَ .