Musnad Ahmad 1153:579

Ali ibn Bahr narrated to us, he said: Abu Khalid al-Ahmar narrated to us, from Muhammad ibn Ishaq, from Abd al-Rahman ibn al-Qasim, from his father, from Aisha, she said: "The Messenger of Allah, peace and blessings of Allah be upon him, performed the Ifadah (Tawaf al-Ifadah) on his last day when he had prayed Dhuhr. Then he returned to Mina and stayed there for the nights of the days of Tashriq. He would stone the Jamrah when the sun passed the meridian, each Jamrah with seven pebbles, saying 'Allahu Akbar' with every pebble. He would stand at the first and at the second, prolonging the standing and supplicating humbly, and he would stone the third without standing at it."