Sahih al-Bukhari 607
Sahih al-Bukhari · Book 10: Call to Prayers (Adhaan) · To pronounce the wording of Iqama once (in singles) except Qad-qamat-is-Salat
Narrated Abu Qilaba:
حَدَّثَنَا عَلِيُّ بْنُ عَبْدِ اللَّهِ ، حَدَّثَنَا إِسْمَاعِيلُ بْنُ إِبْرَاهِيمَ ، حَدَّثَنَا خَالِدٌ ، عَنْ أَبِي قِلاَبَةَ ، عَنْ أَنَسٍ ، قَالَ أُمِرَ بِلاَلٌ أَنْ يَشْفَعَ، الأَذَانَ، وَأَنْ يُوتِرَ الإِقَامَةَ. قَالَ إِسْمَاعِيلُ فَذَكَرْتُ لأَيُّوبَ فَقَالَ إِلاَّ الإِقَامَةَ .
Anas said, "Bilal was ordered to pronounce the wording of Adhan twice and of Iqama once only." The sub narrator Isma`il said, "I mentioned that to Aiyub and he added (to that), "Except Iqama (i.e. Qadqamat- is-salat which should be said twice).