Sunan an-Nasa'i 2500
سنن النسائي#2500Sahihأَخْبَرَنَا عِمْرَانُ بْنُ مُوسَى، عَنْ عَبْدِ الْوَارِثِ، قَالَ حَدَّثَنَا أَيُّوبُ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، قَالَ فَرَضَ رَسُولُ اللَّهِ صلى الله عليه وسلم زَكَاةَ رَمَضَانَ عَلَى الْحُرِّ وَالْعَبْدِ وَالذَّكَرِ وَالأُنْثَى صَاعًا مِنْ تَمْرٍ أَوْ صَاعًا مِنْ شَعِيرٍ فَعَدَلَ النَّاسُ بِهِ نِصْفَ صَاعٍ مِنْ بُرٍّ .
It was narrated that Ibn 'Umar said:"The Messenger of Allah enjoined Zakah of Ramadan upon the free and the slave, male and female, a Sa[1] of dates or a Sa of barley, so the people considered that equivalent to half a Sa of wheat
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: 23:66