Musnad Ahmad 435:70

Yahya ibn Sa'id narrated to us, from Shu'bah, who said: Qatadah narrated to me, from Abu al-Tufayl, who said: Ibn Abbas and Mu'awiyah performed Hajj. Ibn Abbas began to touch all the corners [of the Kaaba]. Mu'awiyah said: "The Messenger of Allah, peace and blessings of Allah be upon him, only touched these two Yemeni corners." Ibn Abbas replied: "None of its corners are to be abandoned."