مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2072
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated from Ibn ‘Abbas that when the Prophet (ﷺ) prostrated, the whiteness of his armpits could be seen.
Musnad Ahmad 2073Saheeh because of corroborating evidence; this is a da'eef i