Sunan an-Nasa'i 1653
سنن النسائي#1653Sahihأَخْبَرَنَا سُلَيْمَانُ بْنُ سَلْمٍ الْبَلْخِيُّ، قَالَ حَدَّثَنَا النَّضْرُ، قَالَ أَنْبَأَنَا يُونُسُ، عَنْ أَبِي إِسْحَاقَ، عَنِ الأَسْوَدِ، عَنْ أُمِّ سَلَمَةَ، قَالَتْ مَا قُبِضَ رَسُولُ اللَّهِ صلى الله عليه وسلم حَتَّى كَانَ أَكْثَرُ صَلاَتِهِ جَالِسًا إِلاَّ الْمَكْتُوبَةَ . خَالَفَهُ شُعْبَةُ وَسُفْيَانُ وَقَالاَ عَنْ أَبِي إِسْحَاقَ عَنْ أَبِي سَلَمَةَ عَنْ أُمِّ سَلَمَةَ .
It was narrated from Al-Aswad, that Umm Salamah said:"The Messenger of Allah (ﷺ) did not pass away until most of his prayers were offered sitting down, except for the obligatory prayers
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: 20:56