(1) باب الْوَصَايَا
Narrated Al-Aswad:
In the presence of `Aisha some people mentioned that the Prophet (ﷺ) had appointed `Ali by will as his successor. `Aisha said, "When did he appoint him by will? Verily when he died he was resting against my chest (or said: in my lap) and he asked for a wash-basin and then collapsed while in that state, and I could not even perceive that he had died, so when did he appoint him by will?"
Reference: Sahih al-Bukhari 2741
In-book reference: Book 55, Hadith 4
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 4, Book 51, Hadith 4