Sunan an-Nasa'i 608
سنن النسائي#608SahihIt was narrated that 'Abdullah said:"I never saw the Messenger of Allah (ﷺ) combine any two prayers except in Al-Muzdalifah, and on that day he prayed Subh before its time
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 6:115