The Book of Prayers (Kitab Al-Salat)
Muslim :: Book 4 : Hadith 1585
'A'isha reported that the Messenger of Allah (may peace be upon him) would pray in the night for a long time, and when he prayed standing be bowed in a standing posture, and when he prayed sitting, he bowed in a sitting posture.
Source materials are from the University of Southern California MSA site|
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