Musannaf Ibn Abi Shayba 20:54

Abu Bakr narrated to us, he said: Waki’ narrated to us, he said: Sufyan narrated to us, from Isma’il bin Umayyah, he said: The Messenger of Allah, peace and blessings of Allah be upon him, decreed, he said: "The testimony of the *dhi al-tinnah* (the one who holds a grudge) and the *hannah* (the one who is excessively old/senile) is not permissible."