وَعَنْ مَالِكٍ، عَنْ أَبِي الزِّنَادِ، أَنَّ عُمَرَ بْنَ عَبْدِ الْعَزِيزِ، كَتَبَ إِلَى عَبْدِ الْحَمِيدِ بْنِ عَبْدِ الرَّحْمَنِ بْنِ زَيْدِ بْنِ الْخَطَّابِ وَهُوَ عَامِلٌ عَلَى الْكُوفَةِ أَنِ اقْضِ بِالْيَمِينِ مَعَ الشَّاهِدِ ‏.‏

From Malik from Abu'z-Zinad that Umar ibn Abd al-Aziz wrote toAbd al-Hamid ibn Abd ar-Rahman ibn Zayd ibn al-Khattab who was thegovernor of Kufa, "Pronounce judgement on the basis of an oath withone witness." Translation Not Available

Book Ref: Muwatta Imam Malik Book 36 Hadith 1410
Web Ref:  Muwatta Imam Malik Book 36 Hadith 6

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