Chapter 41: Types of Blood-Wit (Kitab Al-Diyat)
Narrated Abu Shurayh al-Khuza' i: The Prophet (ﷺ) said: If a relative of anyone is killed, or if he suffers khabl, which means a wound, he may choose one of the three things: he may retaliate, or forgive, or receive compensation. But if he wishes a fourth (i. e. something more), hold his hands. After this whoever exceeds the limits shall be in grave penalty.
Sunan Abi Dawud 4496