Bulugh al-MaramChapter 2Hadith 527
Full Sharh — Bulugh al-Maram 527
وَلِأَبِي نُعَيْمٍ فِي "مُسْتَخْرَجِ مُسْلِمٍ": { كَانَ إِذَا كَانَ فِي سَفَرٍ, فَزَالَتْ اَلشَّمْسُ صَلَّى اَلظُّهْرَ وَالْعَصْرَ جَمِيعًا, ثُمَّ اِرْتَحَلَ }
English Translation
Abu Nu'aim has in his Mustakhraj of Muslim, "While on a journey, if the sun declined he (ﷺ) used to pray Zuhr and 'Asr together and then continue his journey."
Source
Bulugh al-Maram(بلوغ المرام)
The Book of Prayer
Hadith Number
527