Musannaf Ibn Abi Shayba 18:362

Abu Bakr narrated to us, he said: Isma'il bin Ibrahim narrated to us, from al-Walid bin Abi Hisham, from Abu Bakr bin Muhammad bin 'Amr bin Hazm, he said: 'Umar said: "Every shot that penetrates a limb, there is in it one-third of the blood money (diyah) of that limb."