732
Sahih+3
It was narrated that Abu Rafi' said:"I saw Bilal calling the Adhan in fron of Allah's Messenger, (saying the phrases) two by two, and saying each phrase once in the Iqamah
SahihAl-Albani
Sahih LighairihiMuhammad Fouad Abd al-Baqi
Sunan Ibn MajahHadith 732