Sahih Al Bukhari – Book of Characteristics Of Prayer

Volumn 001, Book 012, Hadith Number 767. 
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Narated By Aiyub

: Abu Qilaba RaziAllah Anhusaid, "Malik bin Huwairith RaziAllah Anhuused to demonstrate to us the prayer of the Prophet at times other than that of the compulsory prayers. So (once) he stood up for prayer and performed a perfect Qiyam (standing and reciting from the Holy Qur'an) and then bowed and performed bowing perfectly; then he raised his head and stood straight for a while." Abu Qilaba added, "Malik bin Huwairith in that demonstration prayed like this Sheikh of ours, Abu Yazid." Abu, Yazid used to sit (for a while) on raising his head from the second prostration before getting up.