The Book of Transactions
وَحَدَّثَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، حَدَّثَنَا لَيْثٌ، ح وَحَدَّثَنَا ابْنُ رُمْحٍ، أَخْبَرَنَا اللَّيْثُ، عَنْ نَافِعٍ، عَنِ ابْنِ عُمَرَ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " أَيُّمَا امْرِئٍ أَبَّرَ نَخْلاً ثُمَّ بَاعَ أَصْلَهَا فَلِلَّذِي أَبَّرَ ثَمَرُ النَّخْلِ إِلاَّ أَنْ يَشْتَرِطَ الْمُبْتَاعُ " .Ibn Umar (Allah be pleased with them) reported Allah's Apostle (ﷺ) as saying:Whosoever grafts the tree and then sells its roots, its fruit will belong to one who grafts it except when provision is laid down by the buyer
From Sahih Muslim, whose reports the scholars accept as authentic.