Sahih al-Bukhari, Volume 3, Book 39, Hadith 522 (USC-MSA) ⓘ
Narrated Ibn `Umar: The Prophet made a deal with the people of Khaibar that they would have half the fruits and vegetation of the land they cultivated.
حَدَّثَنَا مُسَدَّدٌ، حَدَّثَنَا يَحْيَى بْنُ سَعِيدٍ، عَنْ عُبَيْدِ اللَّهِ، حَدَّثَنِي نَافِعٌ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ قَالَ عَامَلَ النَّبِيُّ صلى الله عليه وسلم خَيْبَرَ بِشَطْرِ مَا يَخْرُجُ مِنْهَا مِنْ ثَمَرٍ أَوْ زَرْعٍ.
also referenced under: Book 41, Hadith 10 (In-Book) & Hadith 2329 (DarusSalam)