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darimi:3473Abū al-Mughīrah > ʿUtbah b. Ḍamrah b. Ḥabīb from his father

[Machine] "He used to, when he recited a Surah, follow it with saying 'Say: He is Allah, the One.'"  

الدارمي:٣٤٧٣أَخْبَرَنَا أَبُو الْمُغِيرَةِ عَنْ عُتْبَةَ بْنِ ضَمْرَةَ بْنِ حَبِيبٍ عَنْ أَبِيهِ

«أَنَّهُ كَانَ إِذَا قَرَأَ سُورَةً فَخَتَمَهَا أَتْبَعَهَا بِقُلْ هُوَ اللَّهُ أَحَدٌ»