حَدَّثَنَا مُسْلِمُ بْنُ إِبْرَاهِيمَ، حَدَّثَنَا أَبَانُ، - يَعْنِي الْعَطَّارَ - حَدَّثَنَا قَتَادَةُ، عَنِ النَّضْرِ بْنِ أَنَسٍ، عَنْ بَشِيرِ بْنِ نَهِيكٍ، عَنْ أَبِي هُرَيْرَةَ، قَالَ قَالَ النَّبِيُّ صلى الله عليه وسلم ‏"‏ مَنْ أَعْتَقَ شَقِيصًا فِي مَمْلُوكِهِ فَعَلَيْهِ أَنْ يُعْتِقَهُ كُلَّهُ إِنْ كَانَ لَهُ مَالٌ وَإِلاَّ اسْتُسْعِيَ الْعَبْدُ غَيْرَ مَشْقُوقٍ عَلَيْهِ ‏"‏ ‏.‏

Abu Hurairah reported the Prophet (PBUH) as saying: If anyone emancipates a share in his slave, he should completely emancipate him if he has money; but if he has none, then slave will be required to work (to pay for his freedom), but he must not be overburdened. Translation Not Available

Book Ref: Sunan Abi Dawud Book 31 Hadith 3937
Web Ref:  Sunan Abi Dawud Book 30 Hadith 3926