Sahih Bukhari
4871
Narrated Abu 'Is-haq: A man asked Al-Aswad, 'is it 'Fahal min-Muddakir' or'..Mudhdhakir? Al Aswad replied, 'I have heard `Abdullah bin Masud reciting it, 'Fahal-min Muddakir'; I too, heard the Prophet reciting it 'Fahal-min-Muddakir' with 'd'. ..
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