The Messenger of Allah ﷺ said, "The day of breaking the fast is the day the people break their fast, and the day of sacrifice is the day the people offer their sacrifice."
حدثنا يحيى بن موسى حدثنا يحيى بن اليمان عن معمر عن محمد بن المنكدر
قال رسول الله ﷺ الفطر يوم يفطر الناس والأضحى يوم يضحي الناس
No references are available.
[Sahih] It is found in Sharh al-Sunnah by Baghawi, 6/247, no. 1725, via the route of Tirmidhi, with the same wording. The hadith has many corroborating narrations, see no. 697.