Musnad Abu Ya'la al-Mawsili 202:1

A man broke another man’s mouth during the time of Mu’awiyah, and he was offered his blood money, but he refused to accept it until he was given three times [the amount]. A man said, "I heard the Messenger of Allah, peace and blessings of Allah be upon him, say: 'Whoever gives charity for blood or less than that, it will be an expiation for him from the day he was born until the day he gave the charity.'"