Sunan an-Nasa'i 4648
سنن النسائي#4648Sahihأَخْبَرَنَا مُحَمَّدُ بْنُ إِدْرِيسَ، قَالَ حَدَّثَنَا عُمَرُ بْنُ حَفْصِ بْنِ غِيَاثٍ، قَالَ حَدَّثَنَا أَبِي، عَنْ أَبِي عُمَيْسٍ، قَالَ حَدَّثَنِي عَبْدُ الرَّحْمَنِ بْنُ مُحَمَّدِ بْنِ الأَشْعَثِ، عَنْ أَبِيهِ، عَنْ جَدِّهِ، قَالَ عَبْدُ اللَّهِ سَمِعْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم يَقُولُ " إِذَا اخْتَلَفَ الْبَيِّعَانِ وَلَيْسَ بَيْنَهُمَا بَيِّنَةٌ فَهُوَ مَا يَقُولُ رَبُّ السِّلْعَةِ أَوْ يَتْرُكَا " .
Abdullah said:"I heard the Messenger of Allah say: 'If the two parties to a transaction disagree, and neither of them has any proof, then it is as the owner of the goods says, or they may cancel it
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: 44:200