Sunan an-Nasa'i 1678
سنن النسائي#1678SahihIt was narrated that Abu Hurairah said:"My closest friend advised me to do three things: 'To pray witr at the beginning of the night, to pray two rak'ahs of Fajr and to fast three days of each month
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: 20:81