TABARANI 21743:
from Ummih Um Kulthūm b. ʿUqbah b. Abū Muʿayṭ —
[Machine] Al-Qa'nabi reported that Muhammad ibn Abdullah ibn Muslim ibn Akhi Al-Zuhri narrated from his uncle, Ibn Shihab, who narrated from Humaid ibn Abdul Rahman ibn Auf, who narrated from his mother, Umm Kulthum bint Uqbah ibn Abi Muayt. She reported that the Messenger of Allah ﷺ was asked about the verse "Say, He is Allah, the One." He replied, "It is equivalent to one-third of the Quran, or it is like the whole Quran."
الطبراني ٢١٧٤٣:
عن امه ام كلتهوم بن عقبه بن ابو معيط —
ثنا الْقَعْنَبِيُّ ثنا مُحَمَّدُ بْنُ عَبْدِ اللهِ بْنِ مُسْلِمٍ ابْنُ أَخِي الزُّهْرِيِّ عَنْ عَمِّهِ ابْنِ شِهَابٍ عَنْ حُمَيْدِ بْنِ عَبْدِ الرَّحْمَنِ بْنِ عَوْفٍ عَنْ أُمِّهِ أُمِّ كُلْثُومٍ بِنْتِ عُقْبَةَ بْنِ أَبِي مُعَيْطٍ أَنَّ رَسُولَ اللهِ ﷺ سُئِلَ عَنْ قُلْ هُوَ اللهُ أَحَدٌ فَقَالَ ثُلُثُ الْقُرْآنِ أَوْ تَعْدِلُهُ
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