Abu Dawud Book 2, Hadith Number 530.
Chapter : Not known.
Narated By Umm Salamah, Ummul Mu’minin : The Apostle of Allah (PBUH) taught me to say when the adhan for the sunset prayer was called; “O Allah, this is the time when Thy night comes on, Thy day retires, and the voices of Thy summoners are heard, so forgive me.”