Sunan an-Nasa'i 248
سنن النسائي#248SahihAishah narrated concerning the Ghusl of the Prophet (ﷺ) from Janabah, that he used to wash his hands and perform Wudu', then he would run (his fingers) through his (hair on his) head so that it reaches all of his hair, then he would pour water over his entire body
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 ZaiIsnaad Sahih
In-book reference: 1:249