Musnad Ahmad 30:2347

Ghassan narrated to us, Hammad ibn Salamah narrated to us, from Muhammad ibn Amr, from Abu Salamah, from Abu Hurairah, from the Prophet, may Allah bless him and grant him peace; and from Yunus, from al-Hasan, from the Prophet, may Allah bless him and grant him peace, who said: "If one of you hears the call to prayer (Adhan) while the vessel is in his hand, let him not put it down until he has satisfied his need from it."