Sunan an-Nasa'i 628
سنن النسائي#628Hasanأَخْبَرَنَا عَمْرُو بْنُ عَلِيٍّ، قَالَ حَدَّثَنَا يَحْيَى، قَالَ حَدَّثَنَا شُعْبَةُ، قَالَ حَدَّثَنِي أَبُو جَعْفَرٍ، عَنْ أَبِي الْمُثَنَّى، عَنِ ابْنِ عُمَرَ، قَالَ كَانَ الأَذَانُ عَلَى عَهْدِ رَسُولِ اللَّهِ صلى الله عليه وسلم مَثْنَى مَثْنَى وَالإِقَامَةُ مَرَّةً مَرَّةً إِلاَّ أَنَّكَ تَقُولُ قَدْ قَامَتِ الصَّلاَةُ قَدْ قَامَتِ الصَّلاَةُ .
It was narrated that Ibn 'Umar said:"At the time of the Messenger of Allah (S.A.W) the phrases of the Adhan were said twice and the phrases of the Iqamah were said once, except that you should say: 'Qad Qamatis-Salah, Qad Qamatis-Salah (prayer is about to begin, prayer is about to begin)
Scholarly Authentication
The label above is the grade most of these scholars gave — one dissenting opinion no longer speaks for all of them. If any scholar calls a narration fabricated, that verdict is shown instead, whatever the others say. Each scholar's own wording:
In-book reference: 7:3