Musannaf Ibn Abi Shayba 17:1029

Abu Bakr narrated to us, he said: Ali bin Hafs narrated to us, he said: Ibn Abi Dhi'b informed us, from Uthman bin Ubaydullah, a freed slave of Sa'd bin Abi Waqqas, who said: I saw Ibn Umar, Abu Hurayrah, Abu Qatadah, and Abu Usayd al-Sa'idi passing by us while we were at the school, and we would smell the scent of *al-'abeer* from them, and it is *al-khuluq* (a type of perfume).