سُنَنُ النَّسَائِيِّ
Sunan an-Nasa’i 4469
The Book of Financial Transactions
Mentioning the Differneces Reported From Nafi
أَخْبَرَنَا عَمْرُو بْنُ عَلِيٍّ، قَالَ حَدَّثَنَا عَبْدُ الأَعْلَى، قَالَ حَدَّثَنَا سَعِيدٌ، عَنْ أَيُّوبَ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَالَ الْبَيِّعَانِ بِالْخِيَارِ مَا لَمْ يَفْتَرِقَا أَوْ يَقُولَ أَحَدُهُمَا لِلآخَرِ اخْتَرْ .
It was a narrated from Ayyub, from Nafi from Ibn 'Umar that the Messenger of Allah said: "The Messenger of Allah said: "The two parties to a transaction both have the choice who long as they have not separated or one of them says to the other: 'Decide!"' (Sahih )
Sunan an-Nasa'i, 4469