Muwatta Malik, Book 20, Hadith 733 (In-Book)

Yahya related to me from Malik from Nafi that Abdullah ibn Umar once entered ihram at al-Fur.

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، أَهَلَّ مِنَ الْفُرْعِ ‏.‏

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also referenced under: Book 20, Hadith 25 (USC-MSA)