Muwatta Malik, Book 43, Hadith 1573 (In-Book)

Yahya related to me from Malik from Rabia ibn Abi Abd ar-Rahman that Abdullah ibn az-Zubayr allowed retaliation for a head wound which splintered the bone.

وَحَدَّثَنِي يَحْيَى، عَنْ مَالِكٍ، عَنْ رَبِيعَةَ بْنِ أَبِي عَبْدِ الرَّحْمَنِ، أَنَّ عَبْدَ اللَّهِ بْنَ الزُّبَيْرِ، أَقَادَ مِنَ الْمُنَقَّلَةِ ‏.‏

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also referenced under: Book 43, Hadith 6 (USC-MSA)