Sunan Abu Dawud
1017
Sahih+3

Ibn ‘Umar said :The Messenger of Allah (ﷺ) led us in prayer and gave the salutation after two rakahs of prayer. He narrated this tradition like that of Ibn Sirin from Abu Hurairah. This version adds; he gave the salutation and prostrated two prostrations due to forgetfulness

SahihAl-Albani
SahihMuhammad Muhyi Al-Din Abdul Hamid