Musannaf Ibn Abi Shayba 13:3375

Abu Bakr narrated to us, he said: Muhammad ibn Bishr narrated to us, he said: Sa’id narrated to us, from Qatadah, from Jabir ibn Zayd, from Ibn Abbas, who said: "The uncircumcised (al-aqlaf), his testimony is not permissible, his prayer is not accepted, and his slaughtered animal is not to be eaten." He (the narrator) said: And al-Hasan did not hold that view.