Sahih Muslim
The Book of Transactions (Kitab Al-Buyu)
Book Number: 010 / Hadith Number: 3701
Nafi reported on the authority of Ibn Umar (Allah be pleased with them) that the Messenger of Allah (may peace be upon him) said: Whichever tree is bought with its roots, and if it is fecundatedits fruit would belong to one who has grafted it except when the provision is laid down by the buyer.