Musnad Ahmad 907:93

Abdullah narrated to us, Shayban ibn Abi Shaybah narrated to us, Hammad—meaning Ibn Salamah—narrated to us, Simak ibn Harb narrated to us, from Jabir ibn Samurah, who said: They used to say: Yathrib and al-Madinah. The Prophet, peace and blessings of Allah be upon him, said: "Indeed, Allah has named it Taybah."