Musannaf Ibn Abi Shayba 18:231

Abu Bakr narrated to us, he said: Waki’ narrated to us, he said: Sufyan narrated to us, from Zayd ibn Aslam, from Muslim ibn Jundub, from Aslam, the freed slave of Umar, he said: I heard Umar saying upon the pulpit: "Regarding the collarbone, there is a camel."