Musnad Ahmad 931:6

Abdullah narrated to us, Muhammad ibn al-Muthanna Abu Musa al-Anazi narrated to us, Abu Dawud narrated to us, Kharijah ibn Mus'ab narrated to us, from Yunus ibn Ubayd, from al-Hasan, from Uti, from Ubayy, from the Prophet (peace and blessings of Allah be upon him), who said: "For wudu (ablution), there is a devil called al-Walahan, so fear him," or he said, "so beware of him."