Sahih Muslim Book 15, Hadith Number 4102.

Chapter : He who emancipates his share in the slave.

Ibn ‘Umar reported Allah’s Messenger (may peace be upon him) as saying: He who gives up his share in a slave, and has enough money to pay the full price of the slave, then full emancipation devolves upon him; but if he has not the money, then he emancipated what he emancipated.