Sunan Ibn Majah - سنن ابن ماجه
3. The Book of the Adhan and the Sunnah Regarding It - كتاب الأذان والسنة فيها
6) Chapter: Saying The Phrases Of The Iqamah Once
It was narrated that Anas bin Malik said:
"They looked for something by means of which they could call out informing of (the time of) the prayer. Then Bilal was commanded to say the phrases of the Adhan twice and the phrases of the Iqamah once."
6) باب إِفْرَادِ الإِقَامَةِ
حَدَّثَنَا عَبْدُ اللَّهِ بْنُ الْجَرَّاحِ، حَدَّثَنَا الْمُعْتَمِرُ بْنُ سُلَيْمَانَ، عَنْ خَالِدٍ الْحَذَّاءِ، عَنْ أَبِي قِلاَبَةَ، عَنْ أَنَسِ بْنِ مَالِكٍ، قَالَ الْتَمَسُوا شَيْئًا يُؤْذِنُونَ بِهِ عِلْمًا لِلصَّلاَةِ فَأُمِرَ بِلاَلٌ أَنْ يَشْفَعَ الأَذَانَ وَيُوتِرَ الإِقَامَةَ .
