Sahih Muslim 2538
صحيح مسلم#2538SahihIbn 'Umar (Allah be pleased with both of them) reported that the Messenger of Allah (ﷺ) had two Mu'adhdhins, Bilal and son of Umm Maktum, the blind. The Messenger of Allah (ﷺ) said:Bilal announces Adhan at (the fag end of the) night (i. e. Sahri), so eat and drink till the son of Umm Maktum announces Adhan. And he (the narrator) said: And the (difference of time) between their (Adhans) was not more than this that one climbed down (from the minaret) and the other climbed up (to announce Adhan)
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: 13:44