From Sahih Bukhari (Hadith 5217):
Narrated `Aisha:that during his fatal ailment, Allah's Messenger (ﷺ), used to ask his wives, "Where shall I stay tomorrow? Where shall I stay tomorrow?" He was looking forward to Aisha's turn. So all his wives allowed him to stay where he wished, and he stayed at `Aisha's house till he died there. `Aisha added: He died on the day of my usual turn at my house. Allah took him unto Him while his head was between my chest and my neck and his saliva was mixed with my saliva
Reference: Bukhari 5217