Sunan an-Nasa'i, Book 6, Hadith 615 (In-Book) ⓘ
It was narrated that 'Abdullah said: "I never saw the Messenger of Allah combine any two prayers except in Al-Muzdalifah, and on that day he prayed Subh before its time."
أَخْبَرَنَا قُتَيْبَةُ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنِ الأَعْمَشِ، عَنْ عُمَارَةَ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ يَزِيدَ، عَنْ عَبْدِ اللَّهِ، قَالَ مَا رَأَيْتُ النَّبِيَّ صلى الله عليه وسلم جَمَعَ بَيْنَ صَلاَتَيْنِ إِلاَّ بِجَمْعٍ وَصَلَّى الصُّبْحَ يَوْمَئِذٍ قَبْلَ وَقْتِهَا .
also referenced under: Volume 1, Book 6, Hadith 609 (DarusSalam)