بُلُوغُ الْمَرَامِ
Bulugh al-Maram 485
The Book of Prayer
عَنْ عَائِشَةَ رَضِيَ اَللَّهُ عَنْهَا قَالَتْ: قَالَ رَسُولُ اَللَّهِ - صلى الله عليه وسلم -{ الْفِطْرُ يَوْمَ يُفْطِرُ اَلنَّاسُ, وَالْأَضْحَى يَوْمَ يُضَحِّي اَلنَّاسُ } رَوَاهُ اَلتِّرْمِذِيُّ [1] .
Narrated 'Aishah (RA): Allah's Messenger (ﷺ) said: "('Eid) al-Fitr is the day on which the people break the fast, and ('Eid) al-Adha is the day the people offer sacrifices." [Reported by at-Tirmidhi].
Sunnah.com reference: Book 2, Hadith 410