Sunan an-Nasa'i, Hadith 1447 ⓘ
It was narrated from Anas bin Malik that he said: "I prayed two rak'ahs with the Messenger of Allah in Mina, and with Abu Bakr and 'Umar, and two rak'ahs with 'Uthman at the beginning of his Caliphate."
أَخْبَرَنَا 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 .
also referenced under: Book 15, Hadith 15 (In-Book) & Volume 2, Book 15, Hadith 1448 (DarusSalam)