Sunan an-Nasa'i 989
سنن النسائي#989Sahihأَخْبَرَنَا مُحَمَّدُ بْنُ سَلَمَةَ، قَالَ حَدَّثَنَا ابْنُ وَهْبٍ، عَنْ عَمْرِو بْنِ الْحَارِثِ، عَنْ أَبِي الأَسْوَدِ، أَنَّهُ سَمِعَ عُرْوَةَ بْنَ الزُّبَيْرِ، يُحَدِّثُ عَنْ زَيْدِ بْنِ ثَابِتٍ، أَنَّهُ قَالَ لِمَرْوَانَ يَا أَبَا عَبْدِ الْمَلِكِ أَتَقْرَأُ فِي الْمَغْرِبِ بِـ { قُلْ هُوَ اللَّهُ أَحَدٌ } وَ { إِنَّا أَعْطَيْنَاكَ الْكَوْثَرَ } قَالَ نَعَمْ . قَالَ فَمَحْلُوفَةٌ لَقَدْ رَأَيْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقْرَأُ فِيهَا بِأَطْوَلِ الطُّولَيَيْنِ { المص } .
It was narrated from Zaid bin Thabit that :He said to Marwan: "O Abu Abdul-Malik, do you recite: 'Say: He is Allah, (the) One' and 'Verily, We have granted you Al-Kawthar' in maghrib?" He said: "Yes." He (Zaid) said: "I swear by Allah, I saw the Messenger of Allah (ﷺ) reciting the longer of the two long surahs in it: 'Alif-Lam-Mim-Sad
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: 11:114