Sunan Abu Dawud
3940
Sahih+3

Abd Allah b. 'Umar reported the Messenger of Allah (ﷺ) as saying:If anyone emancipates his share in slave, a fair price for the slave should be fixed, give his partners their shares, and the slave be thus emancipated. Otherwise he is emancipated to the extent of the share which he emancipated

SahihAl-Albani
SahihMuhammad Muhyi Al-Din Abdul Hamid