Al-Kāfi - Volume 4 > The Days of al-Nahr (slaughtering the offering, 10th of Dhu al-Hajjah) offering Sacrifice
Hadith #2

2ـ عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ جَمِيلِ بْنِ دَرَّاجٍ عَنْ مُحَمَّدِ بْنِ مُسْلِمٍ عَنْ أَبِي جَعْفَرٍ (عَلَيْهِ السَّلاَم) قَالَ الأَضْحَى يَوْمَانِ بَعْدَ يَوْمِ النَّحْرِ وَيَوْمٌ وَاحِدٌ بِالأَمْصَارِ.

2. Ali ibn Ibrahim has narrated from his father from ibn abu ‘ Umayr from Jamil ibn Darraj from Muhammad ibn Muslim who has said the following: “Abu Ja‘far, ‘Alayhi al-Salam, ‘has said, ‘Al-Adha’ is for two days after the day of al-Nahr (slaughtering the offering on 10th of Dhu al-Hajjah) and it is one day in the cities/”NOTE: Fatwa best explains Hadith 1-2 of this Chapter.