Sunan an-Nasa'i — The Book of Purification — Hadith No: 33
Translation
It was narrated that 'Aishah said:"They say that the Prophet (ﷺ) made a will for 'Ali,[1] but he called for a basin in which to urinate, then he went flaccid suddenly (and died), so how could he leave a will?!" The Shaikh said: Azhar (one of the narrators) is Ibn Sa'd As-Samman. [1] Meaning, appointing him as the Khalifah