Sunan Ibn Majah, Volume 3, Book 21, Hadith 2644 (DarusSalam) ⓘ
It was narrated from 'Amr bin Shu'aib, from his grandfather, that : the Messenger of Allah ruled that the blood money for the people of the book is half of that of the blood money for the Muslims, and they are the Jews and Christians.
حَدَّثَنَا هِشَامُ بْنُ عَمَّارٍ، حَدَّثَنَا حَاتِمُ بْنُ إِسْمَاعِيلَ، عَنْ عَبْدِ الرَّحْمَنِ بْنِ عَيَّاشٍ، عَنْ عَمْرِو بْنِ شُعَيْبٍ، عَنْ أَبِيهِ، عَنْ جَدِّهِ، . أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم قَضَى أَنَّ عَقْلَ أَهْلِ الْكِتَابَيْنِ نِصْفُ عَقْلِ الْمُسْلِمِينَ وَهُمُ الْيَهُودُ وَالنَّصَارَى .
also referenced under: Hadith 2644 (Reference) & Book 21, Hadith 2746 (In-Book)