مُسْنَدُ أَحْمَدَ
Musnad Ahmad 1618
Musnad Abu Ishaq Sa'd bin Abi Waqqas
It was narrated from ‘Amir bin Sa"d that his father said: I saw the Messenger of Allah (ﷺ) say salam to his right and to his left.
Musnad Ahmad 1619Sahih because of corroborating evidence, this is a Da'if isn