حَدَّثَنَا الْحَسَنُ بْنُ عَلِيٍّ، حَدَّثَنَا سَعِيدُ بْنُ عَامِرٍ، عَنِ ابْنِ أَبِي عَرُوبَةَ، عَنْ قَتَادَةَ، بِإِسْنَادِ شُعْبَةَ مِثْلَهُ زَادَ ثُمَّ إِنَّ الْحَسَنَ نَسِيَ هَذَا الْحَدِيثَ فَكَانَ يَقُولُ " لاَ يُقْتَلُ حُرٌّ بِعَبْدٍ " .
Qatadah transmitted the tradition mentioned above through a chain of narrators like that of Shu'bah. This version adds: Then al-Hasan forgot this tradition, and he used to say: A free man is not to be killed for a slave. Translation Not Available
Book Ref: Sunan Abi Dawud Book 41 Hadith 4517
Web Ref: Sunan Abi Dawud Book 40 Hadith 4503