Al-Kāfi
Hadith 9755- عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنِ ابْنِ أَبِي عُمَيْرٍ عَنْ حَفْصِ بْنِ الْبَخْتَرِيِّ عَنْ أَبِي عَبْدِ اللهِ (عَلَيْهِ السَّلام) قَالَ الصُّلْحُ جَائِزٌ بَيْنَ النَّاسِ.
5. Ali ibn Ibrahim has narrated from his father from Ibn Abi ‘Umayr from Hafs al-Bakhtariy who has said the following: “Abu ‘Abd Allah (a.s.), has said, ‘Settlement by means of mutual agreement is permissible for people.’”