(83) بَابُ مَرَضِ النَّبِيِّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ وَوَفَاتِهِ
Narrated Aisha:
Whenever Allah's Messenger (ﷺ) became ill, he used to recite the Muawidhatan (i.e. the last two surahs of the Qur'an) and blow his breath over himself (after their recitation ) and rubbed his hands over his body. So when he was afflicted with his fatal illness. I started reciting the Muawidhatan and blowing my breath over him as he used to do and then I rubbed the hand of the Prophet (ﷺ) over his body.
Reference: Sahih al-Bukhari 4439
In-book reference: Book 64, Hadith 460
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 5, Book 59, Hadith 723