Sunan an-Nasa'i 2369
سنن النسائي#2369Sahihأَخْبَرَنَا زَكَرِيَّا بْنُ يَحْيَى، قَالَ حَدَّثَنَا أَبُو كَامِلٍ، قَالَ حَدَّثَنَا أَبُو عَوَانَةَ، عَنْ عَاصِمِ بْنِ بَهْدَلَةَ، عَنْ رَجُلٍ، عَنِ الأَسْوَدِ بْنِ هِلاَلٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ أَمَرَنِي رَسُولُ اللَّهِ صلى الله عليه وسلم بِرَكْعَتَىِ الضُّحَى وَأَنْ لاَ أَنَامَ إِلاَّ عَلَى وِتْرٍ وَصِيَامِ ثَلاَثَةِ أَيَّامٍ مِنَ الشَّهْرِ .
It was narrated that Abu Hurairah said:"The Messenger of Allah commanded me to pray two Rakahs of Duha, and not to sleep until I had prayed witr, and to fast three days each month
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: 22:280