Sunan an-Nasa'i #1108 · The Book of The At-Tatbiq (Clasping One's Hands Together)

Sunan an-Nasa'iIt was narrated from 'Ubaidullah bin Abdullah bin Aqram that his father said
Sunan an-Nasa'i · Book 12 · The Book of The At-Tatbiq (Clasping One's Hands Together)
Sunan an-Nasa'i · كتاب 12 · كتاب التطبيق
"I prayed with the Messenger of Allah (ﷺ) and I used to see the whiteness of his armpits when he prostrated
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 ‏.‏
Reference : Sunan an-Nasa'i 1108In-book reference : Book 12, Hadith 80