أَخْبَرَنَا عَلِيُّ بْنُ حُجْرٍ، قَالَ أَنْبَأَنَا إِسْمَاعِيلُ، قَالَ حَدَّثَنَا دَاوُدُ بْنُ قَيْسٍ، عَنْ عُبَيْدِ اللَّهِ بْنِ عَبْدِ اللَّهِ بْنِ أَقْرَمَ، عَنْ أَبِيهِ، قَالَ صَلَّيْتُ مَعَ رَسُولِ اللَّهِ صلى الله عليه وسلم فَكُنْتُ أَرَى عُفْرَةَ إِبْطَيْهِ إِذَا سَجَدَ ‏.‏

It was narrated from 'Ubaidullah bin Abdullah bin Aqram that his father said: "I prayed with the Messenger of Allah (PBUH) and I used to see the whiteness of his armpits when he prostrated." Translation Not Available

Book Ref: Sunan An Nisai Book 12 Hadith 1108
Web Ref:  Sunan An Nisai Vol 2 Book 12 Hadith 1109

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