Musnad Ahmad 32:545

Harun ibn Ma'ruf narrated to us, Abdullah ibn Wahb narrated to us, he said: And Amr ibn al-Harith informed me, from Bukayr ibn al-Ashajj, that al-Dahhak ibn Abdullah al-Qurashi narrated to him, from Anas ibn Malik, that he said: I saw the Messenger of Allah, peace and blessings of Allah be upon him, on a journey, he prayed the Duha prayer [as] eight rak'ahs. When he finished, he said: "I prayed a prayer of desire and fear. I asked my Lord for three things; He granted me two and withheld one from me. I asked Him not to afflict my nation with years [of famine], and He did. I asked Him not to let their enemy overcome them, and He did. And I asked Him not to clothe them in sects [i.e., cause them to divide into factions], but He refused me." *** Harun narrated to us—Abu Abd al-Rahman said: And I heard it from Harun more than once—Abdullah ibn Wahb narrated to us, he said: And Jarir ibn Hazim narrated to me that he heard Qatadah ibn Di'amah say: Anas ibn Malik narrated to us that a man came to the Prophet, peace and blessings of Allah be upon him, having performed ablution, but he left [a spot] on his foot the size of a fingernail. The Messenger of Allah, peace and blessings of Allah be upon him, said to him: "Go back and perform your ablution well."