(4) باب مَا يُقَالُ إِذَا أَذَّنَ الْمُؤَذِّنُ
It was narrated that Abu Sa'eed Al-Khudri said:
"The Messenger of Allah said: 'When you hear the call (to prayer), say what the Mu'adh-dhin says.'" (IT)
Reference (IT): Sunan Ibn Majah 720 (IT)
In-book reference (IT): Book 3, Hadith 15 (IT)
English translation (IT): Vol. 1, Book 3, Hadith 720 (IT)