Abu Dawud
Prayer
Book Number: 002 / Hadith Number: 743
Narated By Ali ibn AbuTalib : When the Apostle of Allah (pbuh) stood for offering the obligatory prayer, he uttered the takbir (Allah is most great) and raised his hands opposite to his shoulders; and he did like that when he finished recitation (of the Qur'an) and was about to bow; and he did like that when he rose after bowing; and he did not raise his hands in his prayer while he was in his sitting position.
When he stood up from his prostrations (at the end of two rak'ahs), he raised his hands likewise and uttered the takbir (Allah is most great) and raised his hands so as to bring them up to his shoulders, as he uttered the takbir in the beginning of the prayer.