The Messenger of Allah ﷺ commanded us to greet our leaders with peace and to greet one another with peace.
حدثنا عبدة بن عبد الله حدثنا علي بن القاسم أنبأنا همام عن قتادة عن الحسن
أمرنا رسول الله ﷺ أن نسلم على أئمتنا وأن يسلم بعضنا على بعض
No references are available.
Grading, [Its chain is daif]. Abu Dawud narrated it in the Book of Prayer, chapter "Responding to the Imam," hadith no. 1001, through Qatada with this wording. Hakim graded it sahih, and Dhahabi agreed.Qatada is a mudallis, as noted before at hadith no. 175, and I did not find an explicit statement that he heard this particular hadith directly.