Sunan an-Nasa'i 1640
سنن النسائي#1640SahihIt was narrated that Abu Ishaq said:"I came to Al-Aswad bin Yazid, who was a close friend of mine and said: 'O Abu 'Amr, tell me what the Mother of the Believers told you about the prayer of the Messenger of Allah (ﷺ).' He said: 'She said: "He used to sleep for the first part of the night and stay up for the latter part
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: 20:43