Sunan an-Nasa'i 1447
سنن النسائي#1447Sahihأَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا اللَّيْثُ، عَنْ بُكَيْرٍ، عَنْ مُحَمَّدِ بْنِ عَبْدِ اللَّهِ بْنِ أَبِي سُلَيْمٍ، عَنْ أَنَسِ بْنِ مَالِكٍ، أَنَّهُ قَالَ صَلَّيْتُ مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم بِمِنًى وَمَعَ أَبِي بَكْرٍ وَعُمَرَ رَكْعَتَيْنِ وَمَعَ عُثْمَانَ رَكْعَتَيْنِ صَدْرًا مِنْ إِمَارَتِهِ .
It was narrated from Anas bin Malik that he said:"I prayed two rak'ahs with the Messenger of Allah (ﷺ) in Mina, and with Abu Bakr and 'Umar, and two rak'ahs with 'Uthman at the beginning of his Caliphate
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 15:15