(15) باب يُؤَخِّرُ الظُّهْرَ إِلَى الْعَصْرِ إِذَا ارْتَحَلَ قَبْلَ أَنْ تَزِيغَ الشَّمْسُ
Narrated Anas bin Malik:
Whenever the Prophet (ﷺ) started the journey before noon, he used to delay the Zuhr prayer till the time for the `Asr prayer and then he would dismount and pray them together; and whenever the sun declined before he started the journey he used to offer the Zuhr prayer and then ride (for the journey).
Reference: Sahih al-Bukhari 1111
In-book reference: Book 18, Hadith 31
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 2, Book 20, Hadith 213