Abu Dawud Book 2, Hadith Number 739.
Chapter : Not known.
Narated By Abdullah ibn Abbas : Nadr ibn Kathir as-Sa’di said: Abdullah ibn Tawus prayed at my side in the mosque of al-Khayf. When he made the first prostration, he raised his head after it and raised his hands opposite to his face. This came as something strange for me. I, therefore, said it to Wuhayb ibn Khalid.
Then Wuhayb ibn Khalid said to him: You are doing a thing that I did not see anyone do. Ibn Tawus then replied: I saw my father doing it, and my father said: I saw Ibn Abbas doing it. I do not know but he said: The Prophet (PBUH) used to do it.