Sunan an-Nasa'i #627 · The Book of the Adhan (The Call to Prayer)

Sunan an-Nasa'iIt was narrated that Anas said
Sunan an-Nasa'i · Book 7 · The Book of the Adhan (The Call to Prayer)
Sunan an-Nasa'i · كتاب 7 · كتاب الأذان
"The Messenger of Allah (S.A.W) commanded Bilal to say the phrases of the Adhan twice and the phrases of the Iqamah once
أَخْبَرَنَا قُتَيْبَةُ بْنُ سَعِيدٍ، قَالَ حَدَّثَنَا عَبْدُ الْوَهَّابِ، عَنْ أَيُّوبَ، عَنْ أَبِي قِلاَبَةَ، عَنْ أَنَسٍ، قَالَ إِنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم أَمَرَ بِلاَلاً أَنْ يَشْفَعَ الأَذَانَ وَأَنْ يُوتِرَ الإِقَامَةَ ‏.‏
Reference : Sunan an-Nasa'i 627In-book reference : Book 7, Hadith 2