Sunan an-Nasa'i 477
سنن النسائي#477SahihIt was narrated from Anas bin Malik that the Prophet (ﷺ) prayed Zuhr in Al-Madinah, four Rak'ahs, and he prayed 'Asr in Dhul-Hulaifah, two Rak'ahs
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: 5:30