The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1003

Maimuna, the wife of the Apostle of Allah (may peace be upon him), reported: When the Messenger of Allah (may peace be upon him) prostrated himself, he spread his arms, i. e. he separated them so much that the whiteness of his armpits became visible from behind and when he sat (for Jalsa) he rested on his left thigh.

Source materials are from the University of Southern California MSA site
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