Musnad Ahmad 21:5

Rawh narrated to us, Abu Yunus al-Qushayri Hatim ibn Abi Saghir narrated to us, a man from the descendants of Abd al-Muttalib narrated to me, he said: Ali ibn Abd Allah ibn Abbas came to us, and the sons of Abd al-Muttalib were present with him. He said: I heard Abd Allah ibn Abbas narrating from his father, al-Abbas ibn Abd al-Muttalib, who said: I came to the Messenger of Allah, peace and blessings of Allah be upon him, and said: "O Messenger of Allah, I am your uncle, my age has become advanced." Then he mentioned its meaning.