مُسْنَدُ أَحْمَدَ
Musnad Ahmad 4275
Musnad of Abdullah bin Mas'ood
It was narrated from 'Abdullah that The Prophet (ﷺ) said: “Whoever sees me in a dream, then it is me that he has seen, for verily the Shaitan cannot appear in my form."
Musnad Ahmad 4304Saheeh]