Mishkat al-Masabih #3335

'Amr b. Shu'aib, on his father’s authority, said his grandfather reported God’s Messenger as saying, “If anyone kills a man deliberately he is to be handed over to the relatives of the one who has been killed. If they wish they may kill him, but if they wish they may accept blood wit, which is thirty she-camels in their fourth year, thirty in their fifth year, and forty pregnant she-camels. Any arrangement they make with him is for them to decide.” Tirmidhi transmitted it.