Sunan an-Nasa'i 4708
it was narrated from Abu Salamah and Sulaiman bin Yasar, from some of the Companions of the Messenger of Allah, that:
Qasamah existed during the Jahiliyyah and the Messenger of Allah approved of it as it had been during the Jahiliyyah, and he ruled accordingly among some of the Ansar concerning a victim whom they claimed the Jews of Khaibar had Killed. (Sahih)
Ma'mar contradicted the two of them.
أَخْبَرَنَا مُحَمَّدُ بْنُ هَاشِمٍ، قَالَ حَدَّثَنَا الْوَلِيدُ، قَالَ حَدَّثَنَا الأَوْزَاعِيُّ، عَنِ ابْنِ شِهَابٍ، عَنْ أَبِي سَلَمَةَ، وَسُلَيْمَانَ بْنِ يَسَارٍ، عَنْ أُنَاسٍ، مِنْ أَصْحَابِ رَسُولِ اللَّهِ صلى الله عليه وسلم أَنَّ الْقَسَامَةَ كَانَتْ فِي الْجَاهِلِيَّةِ فَأَقَرَّهَا رَسُولُ اللَّهِ صلى الله عليه وسلم عَلَى مَا كَانَتْ عَلَيْهِ فِي الْجَاهِلِيَّةِ وَقَضَى بِهَا بَيْنَ أُنَاسٍ مِنَ الأَنْصَارِ فِي قَتِيلٍ ادَّعَوْهُ عَلَى يَهُودِ خَيْبَرَ ‏.‏ خَالَفَهُمَا مَعْمَرٌ ‏.‏