Sahih Muslim 2763
صحيح مسلم#2763SahihSalim reported on the authority of his father that a person saw Lailat-ul- Qadr on the 27th (of Ramadan). Thereupon Allah's Apostle (ﷺ) said:I see that your dreams agree regarding the last ten (nights of Ramadan). So seek it on an odd number (of these ten nights)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih Muslim is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 13:269