مُسْنَدُ أَحْمَدَ
Musnad Ahmad 1471
Musnad Abu Ishaq Sa'd bin Abi Waqqas
Ibraheem bin "Abdur-Rahman bin Sa"d bin Abi Waqqas said: On the day of Uhud, I saw on the right of the Messenger of Allah (ﷺ) and on his left, two men in white garments who were fighting to defend him in the fiercest manner. I have never seen them before or since.
Musnad Ahmad 1471Sahih (Darussalam)]