صَحِيحُ مُسْلِمٍ
Sahih Muslim 704 c
The Book of Prayer - Travellers
It is permissible to combine two prayers when traveling
وَحَدَّثَنِي أَبُو الطَّاهِرِ، وَعَمْرُو بْنُ سَوَّادٍ، قَالاَ أَخْبَرَنَا ابْنُ وَهْبٍ، حَدَّثَنِي جَابِرُ بْنُ إِسْمَاعِيلَ، عَنْ عُقَيْلٍ، عَنِ ابْنِ شِهَابٍ، عَنْ أَنَسٍ، عَنِ النَّبِيِّ صلى الله عليه وسلم إِذَا عَجِلَ عَلَيْهِ السَّفَرُ يُؤَخِّرُ الظُّهْرَ إِلَى أَوَّلِ وَقْتِ الْعَصْرِ فَيَجْمَعُ بَيْنَهُمَا وَيُؤَخِّرُ الْمَغْرِبَ حَتَّى يَجْمَعَ بَيْنَهَا وَبَيْنَ الْعِشَاءِ حِينَ يَغِيبُ الشَّفَقُ .
Anas reported that when the Messenger of Allah (ﷺ) had to set out on a journey hurriedly, he delayed the noon prayer to the earlier time for the afternoon prayer, and then he would combine them, and he would delay the sunset prayer to the time when the twilight would disappear and then combine it with the 'Isha' prayer.
Sahih Muslim, 704 cSahihصحيح