Musannaf Ibn Abi Shayba 3:5761

Waki’ narrated to us, he said: Hisham ibn al-Ghazi narrated to us, from Rabi’ah al-Jurashi, from ‘Ata’ ibn Abi Rabah, who said: I said to Ibn Abbas: "Should I shorten [the prayer] to Arafah?" He said: "No." I said: "Should I shorten to Marr?" He said: "No." I said: "Should I shorten to al-Ta’if and to ‘Usfan?" He said: "Yes, and that is forty-eight miles," and he gestured with his hand.