The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1236

Abu Zubair reported: Abdullah b Zubair used to say La ilaha il-Allah at the end of every prayer like the hadith narrated by Ibn Numair and he reported it in the end, and then reported Ibn Zubair saying: The Messenger of Allah (may peace be upon him) uttered La ilaha il-Allah at the end of every prayer.

Source materials are from the University of Southern California MSA site
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