Musannaf Ibn Abi Shayba 28:374

Abu Mu'awiyah narrated to us, he said: Al-A'mash narrated to us, from 'Amr ibn Murrah, from Abu Salih, who used to serve Umm Kulthum bint 'Ali. He said: She said, "O Abu Salih, how would it be if you saw the Commander of the Faithful when a citron was brought to him? Al-Hasan and Al-Husayn went to take a citron from it, so he snatched it from their hands and ordered it to be distributed among the people."