Musnad Ahmad 526:2

'Abd al-Rahman ibn Mahdi narrated to us, he said: Mu'awiyah—meaning Ibn Salih—narrated to us, from Sulayman Abu al-Rabi'—'Abdullah said: My father said: "He is Sulayman ibn 'Abd al-Rahman, from whom Shu'bah and Layth ibn Sa'd narrated"—from al-Qasim, the freed slave of Mu'awiyah, who said: I entered the mosque of Damascus and saw people gathered and an old man speaking to them. I said: "Who is this?" They said: "Sahl ibn al-Hanzaliyyah." Then I heard him say: I heard the Messenger of Allah, peace and blessings of Allah be upon him, say: "Whoever eats meat, let him perform ablution."