Musannaf Ibn Abi Shayba 3:3235

Abu al-Ahwas narrated to us, from ‘Ata’ ibn al-Sa’ib, who said: I prayed the Fajr prayer in this mosque on the day of Fitr. Suddenly, there was Abu ‘Abd al-Rahman and ‘Abd Allah ibn Mughaffal (Ma’qil). When we finished the prayer, they went out, and I went out with them to the prayer ground (al-jabbana).