مُسْنَدُ أَحْمَدَ
Musnad Ahmad 2991
Musnad of 'Abdullah bin al-'Abbas bin 'Abdul-Muttalib from the Prophet
It was narrated that 'lkrimah said: I saw a man enter the mosque, and he stood and prayed. When he raised his head he said takbeer, when he placed his head (on the ground, in prostration) he said takbeer, and when he got up following two rak'ahs he said takbeer. I found that strange, so I went to Ibn 'Abbas and told him about that and he said: May you be bereft of your mother! Isn't that the prayer of the Messenger of Allah (ﷺ)?
Musnad Ahmad 3014its isnad is saheeh]