Sunan Abi Dawud, Hadith 1557

This tradition has also been transmitted by Al Zuhri through a different chain of narrators. This version has “Abu Bakr said its due is the payment of zakat.” He used the word “a rope of a Camel”

حَدَّثَنَا ابْنُ السَّرْحِ، وَسُلَيْمَانُ بْنُ دَاوُدَ، قَالاَ أَخْبَرَنَا ابْنُ وَهْبٍ، أَخْبَرَنِي يُونُسُ، عَنِ الزُّهْرِيِّ، قَالَ قَالَ أَبُو بَكْرٍ إِنَّ حَقَّهُ أَدَاءُ الزَّكَاةِ وَقَالَ عِقَالاً ‏.‏

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also referenced under: Hadith 1552 (Hasan)