The tradition mentioned above has also been transmitted by Simak (b. Harb) with a different chain of narrators and to the same effect. The first version is more perfect. It does not mention the words "at the current rate".
Hadith Referenceسنن ابي داود / كتاب البيوع / 3355
Hadith Gradingزبیر علی زئی:حسن, انظر الحديث السابق (3354)
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