Full Sharh — Sahih Muslim 1590
وَحَدَّثَنِي حَرْمَلَةُ بْنُ يَحْيَى، حَدَّثَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي عَمْرٌو، وَهُوَ ابْنُ الْحَارِثِ عَنِ ابْنِ شِهَابٍ، عَنْ سَالِمِ بْنِ عَبْدِ اللَّهِ، عَنْ أَبِيهِ، عَنْ رَسُولِ اللَّهِ صلى الله عليه وسلم أَنَّهُ صَلَّى صَلاَةَ الْمُسَافِرِ بِمِنًى وَغَيْرِهِ رَكْعَتَيْنِ وَأَبُو بَكْرٍ وَعُمَرُ وَعُثْمَانُ رَكْعَتَيْنِ صَدْرًا مِنْ خِلاَفَتِهِ ثُمَّ أَتَمَّهَا أَرْبَعًا .
English Translation
Salim b. 'Abdullah (b. 'Umar) reported on the authority of his father that Allah's Messenger (ﷺ) observed the prayer of a traveller, i. e. two rak'ahs in Mina, and other places; so did Abu Bakr and 'Umar, and 'Uthman too observed two rak'ahs at the beginning of his caliphate, but he then completed four
Source
Sahih Muslim(صحيح مسلم)
The Book of Prayer - Travellers
Hadith Number
1590