The Book of Fasting (Kitab Al-Sawm)

Muslim :: Book 6 : Hadith 2637

Abdullah b. Umar (Allah be pleased with both of them) reported that the Messenger of Allah (may peace be upon him) used to observe i'tikaf in the last ten days of Ramadan. Nafi' said: Abdullah (Allah be pleased with him) showed me the place in the mosque where the Messenger of Allah (may peace be upon him) used to observe i'tikaf.

Source materials are from the University of Southern California MSA site
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