Jami` at-Tirmidhi 790
جامع الترمذي#790SahihAbu Hurairah and Aishah narrated:"The Prophet would perform I'tikaf during the last ten (days) of Ramadan until Allah took him
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Ahmad Muhammad ShakirSahih
Al-AlbaniSahih
Bashar Awad MaaroufHasan Sahih
Zubair Ali ZaiSahih
In-book reference: 8:109