Sunan an-Nasa'i, Book 44, Hadith 250 (In-Book) ⓘ
It was narrated from Salim, from his father, that the Messenger of Allah said: "Whoever sets free his share of a slave should set him free completely from his own wealth, if he has enough wealth to cover the price of the slave."
أَخْبَرَنَا نُوحُ بْنُ حَبِيبٍ، قَالَ أَنْبَأَنَا عَبْدُ الرَّزَّاقِ، قَالَ أَنْبَأَنَا مَعْمَرٌ، عَنِ الزُّهْرِيِّ، عَنْ سَالِمٍ، عَنْ أَبِيهِ، أَنَّ النَّبِيَّ صلى الله عليه وسلم قَالَ " مَنْ أَعْتَقَ شِرْكًا لَهُ فِي عَبْدٍ أُتِمَّ مَا بَقِيَ فِي مَالِهِ إِنْ كَانَ لَهُ مَالٌ يَبْلُغُ ثَمَنَ الْعَبْدِ " .
also referenced under: Hadith 4698 (Reference) & Volume 5, Book 44, Hadith 4702 (DarusSalam)