Musnad Ahmad 25:1434

Yazid narrated to us, he said: Imran bin Hudair and Mu'adh informed us, he said: Imran—meaning Ibn Hudair—narrated to us, from Abdullah bin Shaqiq, who said: A man stood up to Ibn Abbas and said: "The prayer." He remained silent regarding him. Then he said: "The prayer." He remained silent regarding him. Then he said: "The prayer." Ibn Abbas said: "Are you teaching us about the prayer? We used to combine two prayers with the Messenger of Allah (peace and blessings of Allah be upon him), or during the time of the Messenger of Allah." Mu'adh said: "During the time of the Messenger of Allah (peace and blessings of Allah be upon him)."