Sunan an-Nasa'i, Book 51, Hadith 25 (In-Book)

It was narrated that Abu Idris said: "I saw Anas bin Malik when some Busr which had extra bits were brought to him, and he started to cut them off."

أَخْبَرَنَا سُوَيْدُ بْنُ نَصْرٍ، قَالَ أَخْبَرَنَا عَبْدُ اللَّهِ، عَنْ هِشَامِ بْنِ حَسَّانَ، عَنْ أَبِي إِدْرِيسَ، قَالَ شَهِدْتُ أَنَسَ بْنَ مَالِكٍ أُتِيَ بِبُسْرٍ مُذَنَّبٍ فَجَعَلَ يَقْطَعُهُ مِنْهُ ‏.‏

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