Musnad Ahmad 25:1674

Rawh narrated to us, Ath-Thawri narrated to us, Abdullah bin Uthman bin Khuthaym narrated to us, from Abu at-Tufayl, who said: I was with Mu'awiyah and Ibn Abbas while they were circumambulating the House. Ibn Abbas used to touch the two corners, while Mu'awiyah used to touch all the corners. Ibn Abbas said: "The Messenger of Allah, may Allah bless him and grant him peace, would not touch except these two corners: the Yemeni and the Black [Stone]." Mu'awiyah said: "There is nothing of it that is abandoned."