Sunan an-Nasa'i 1710
سنن النسائي#1710SahihDuwaid bin Nafi' said:" Ibn Shihab informed me, saying: 'Ata bin Yazid narrated to me from Abu Ayyub: That the Prophet (ﷺ) said: 'Witr is a duty, and whoever wants to pray witr with seven (rak'ahs), let him do so; whoever wants to pray witr with five, let him do so, whoever wants to pray witr with three, let him do so; and whoever wants to pray witr with one, let him do so
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
In-book reference: 20:113