Musnad Ahmad 30:371

Ya'qub narrated to us, my father narrated to us, from Ibn Ishaq, 'Iyad ibn Dinar al-Laythi narrated to me—and he was trustworthy—he said: I heard Abu Hurayrah, while he was delivering the sermon to the people on Friday, as a deputy for Marwan ibn al-Hakam over Medina during the days of Hajj, saying: Abu al-Qasim (may Allah bless him and grant him peace) said: "The first group," and he mentioned the hadith.