Sunan an-Nasa'i 992
سنن النسائي#992Hasanأَخْبَرَنَا الْفَضْلُ بْنُ سَهْلٍ، قَالَ حَدَّثَنِي أَبُو الْجَوَّابِ، قَالَ حَدَّثَنَا عَمَّارُ بْنُ رُزَيْقٍ، عَنْ أَبِي إِسْحَاقَ، عَنْ إِبْرَاهِيِمَ بْنِ مُهَاجِرٍ، عَنْ مُجَاهِدٍ، عَنِ ابْنِ عُمَرَ، قَالَ رَمَقْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم عِشْرِينَ مَرَّةً يَقْرَأُ فِي الرَّكْعَتَيْنِ بَعْدَ الْمَغْرِبِ وَفِي الرَّكْعَتَيْنِ قَبْلَ الْفَجْرِ { قُلْ يَا أَيُّهَا الْكَافِرُونَ } وَ { قُلْ هُوَ اللَّهُ أَحَدٌ } .
It was narrated that Ibn Umar said:"I watched the Messenger of Allah (ﷺ)- twenty times- reciting in the two rak'ahs after maghrib 'Say: O you disbelievers' and 'Say: He is Allah, (the) One
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 11:117