Musnad Ahmad 30:1162

Ali ibn Hafs narrated to us, Warqa’ informed us, from Abu al-Zinad, from al-A’raj, from Abu Hurayrah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Ibrahim, the Khalil (intimate friend) of the Most Merciful, was circumcised after eighty years had passed upon him, and he was circumcised with the Qadum (adze)."