Musnad Abu Ya'la al-Mawsili 115:104

Al-Harith ibn Miskin narrated to us, Ibn Wahb narrated to us, from Jarir ibn Hazim, from Qatadah, from Anas: That the Prophet, peace and blessings of Allah be upon him, performed the *aqiqah* for al-Hasan and al-Husayn with two rams.