Musnad Abu Ya'la al-Mawsili 109:148

Abu Khaythama narrated to us, Abd al-Rahman narrated to us, from Sufyan, from Abu al-Zubayr, from Jabir, who said: The Messenger of Allah (peace and blessings of Allah be upon him) departed from Arafah while he was composed, and he commanded composure. He quickened his pace in the valley of Muhassir and said: "Take your rites, for I do not know, perhaps you will not meet me after this year or this day of yours." And he threw [pebbles] the size of pebbles used for throwing (al-khadhf).